0001558370-24-003165 | 10-K | XBRL Viewer

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Summary of significant accounting policies and basis of presentation - Restricted cash (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Summary of significant accounting policies and basis of presentation
Cash on deposit	$ 1,979	$ 1,979
Cash and cash equivalents	47,324	84,265
Restricted cash	1,979	1,979
Cash, cash equivalents, and restricted cash	$ 49,303	$ 86,244	$ 58,162

Stock-based compensation (Details) - shares		3 Months Ended	12 Months Ended
Stock-based compensation (Details) - shares	Jan. 01, 2022	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Jun. 17, 2021
Stock based compensation
Percentage of common stock outstanding	5.00%
Performance Based Restricted Stock Units
Stock based compensation
Conversion of stock shares issued		1
Performance Based Restricted Stock Units \| Tranche 1
Stock based compensation
Vesting percentage			50.00%
Performance Based Restricted Stock Units \| Tranche 2
Stock based compensation
Vesting percentage			50.00%
2021 Incentive Plan
Stock based compensation
Shares authorized for issuance			3,124,544
Increase in common stock reserved	2,750,276		2,954,788
Additional shares authorized for issuance			3,025,220
Shares available for grant			3,128,244	5,786,358
2021 Incentive Plan \| Employee Stock Option [Member]
Stock based compensation
Shares authorized for issuance					5,481,735
Shares available for grant					5,640,711
Stock reserved for issuance upon the exercise of previously granted stock options					158,976

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss	Total
Ending balance (in shares) at Dec. 31, 2022	58,473,660
Beginning balance at Dec. 31, 2021	$ 5	$ 785,049	$ (388,166)	$ (650)	$ 396,238
Beginning Balance (in shares) at Dec. 31, 2021	55,005,523
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock to collaboration partner	$ 1	26,812			26,813
Issuance of stock to collaboration partner (in shares)	2,160,760
Issuance of common stock upon the exercise of stock options		345			345
Issuance of common stock upon the exercise of stock options (in shares)	342,833
Vesting of restricted stock (in shares)	488,758
Vesting of early exercise stock options		1,417			1,417
Vesting of early exercise stock options (in shares)	475,786
Unrealized gain / loss on short-term investments				(1,786)	(1,786)
Foreign currency translation				(26)	(26)
Stock based compensation		10,669			10,669
Net Income (Loss)			(130,932)		(130,932)
Ending balance at Dec. 31, 2022	$ 6	824,292	(519,098)	(2,462)	302,738
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon the exercise of stock options	$ 0	943			943
Issuance of common stock upon the exercise of stock options (in shares)	761,381
Vesting of restricted stock (in shares)	95,877
Vesting of early exercise stock options		$ 943			$ 943
Vesting of early exercise stock options (in shares)	351,521
Vesting of restricted stock units (in shares)	653,262	(393,000)			(393,000)
Unrealized gain / loss on short-term investments				2,602	$ 2,602
Foreign currency translation					(32)
Stock based compensation		$ 14,622			14,622
Net Income (Loss)			(136,673)		(136,673)
Ending balance at Dec. 31, 2023	$ 6	$ 840,407	$ (655,771)	$ 108	$ 184,750
Ending Balance (in shares) at Dec. 31, 2023	60,335,701

Long-term debt

12 Months Ended

Dec. 31, 2023

Long-term debt

Long-term debt

Note 8—Long-term debt

The following is a summary of the Company’s indebtedness:


	December 31, 2023		December 31, 2022
Principal	$	—	$	10,000
Plus: End of term fee		—		395
Less: Debt discount attributable to warrants, net of accretion		—		(8)
Less: Unamortized deferred financing cost and end of term fee, net of accretion		—		(146)
Long-term debt, net	$	—	$	10,241

On September 14, 2020, the Company entered into a $10,000 Term Loan Agreement (as amended, the “Loan Agreement”) with Hercules Capital, Inc. (“Hercules”). Pursuant to the terms of the Loan Agreement, the Company borrowed $10,000 (the “Tranche 1 Advance”) from the lenders at closing. The Company granted Hercules a lien on substantially all of the Company’s assets, excluding intellectual property.

On May 1, 2023, the Company prepaid the Loan Agreement in full. The total amount paid to Hercules in connection with the prepayment was $10,617, which included all outstanding principal, accrued and unpaid interest and end of term and prepayment charges (“the Payoff Amount”). The Payoff Amount included a prepayment charge of $100 (equal to 1.0% of the outstanding principal), and an end of term fee of $395, which was being recognized as interest expense and accreted over the term of the Loan Agreement using the effective interest method. Upon receipt by Hercules of the Payoff Amount on May 1, 2023, all obligations, covenants, debts and liabilities of the Company under the Loan Agreement were satisfied and discharged in full, and the Loan Agreement was terminated.

The Company issued to Hercules warrants to purchase up to an aggregate of 16,112 shares of common stock. The warrants are exercisable for a period of ten years from the date of the issuance of each warrant at a per share exercise price equal to $13.96, subject to certain adjustments as specified in the warrants. The fair value of the warrants at issuance was $46. The Company accounted for the warrants as equity, and the fair value is recorded in additional paid-in capital.

Interest expense of the Loan Agreement is as follows:



	For the Year Ended		For the Year Ended
	December 31, 2023		December 31, 2022
Interest expense	$	540	$	787
Amortization of debt issuance costs, including end of term fee accretion		—		230
	$	540	$	1,017

Included in accrued expenses in the accompanying consolidated balance sheets as of December 31, 2023 and 2022 was $0 and $117 of accrued interest, respectively.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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+ Details

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (136,673)	$ (130,932)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Bristol-Myers Squibb Collaboration (Tables)

12 Months Ended

Dec. 31, 2023

Bristol-Myers Squibb Collaboration

Schedule of transaction price unsatisfied


			Cumulative collaboration		Deferred
Performance obligations:	Transaction price		revenue recognized		collaboration revenue
Option rights	$	109,164	$	-	$	109,164
Research and development services		14,023		(7,434)		6,589
Total		123,187		(7,434)		115,753
Less current portion of deferred revenue		-		-		(4,372)
Total long-term deferred revenue	$	123,187	$	(7,434)	$	111,381

Leases - Other information (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Leases
Operating lease right-of-use asset, net	$ 20,376	$ 28,945
Operating lease liability, current	$ 1,513	$ 475
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued Expenses And Other Liabilities, Current	Accrued Expenses And Other Liabilities, Current
Operating lease liability, long term	$ 46,658	$ 38,698
Total operating lease liability	$ 48,171	$ 39,173

Financial instruments and fair value measurements - Assets measured at fair value (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financial instruments and fair value measurements
Cash equivalents	$ 42,263	$ 77,736
Total assets	256,773	360,814
U.S. Treasury
Financial instruments and fair value measurements
Debt securities	26,114	86,475
Corporate bonds
Financial instruments and fair value measurements
Debt securities	188,396	196,603
Level 1
Financial instruments and fair value measurements
Cash equivalents	42,263	77,736
Total assets	42,263	77,736
Level 2
Financial instruments and fair value measurements
Total assets	214,510	283,078
Level 2 \| U.S. Treasury
Financial instruments and fair value measurements
Debt securities	26,114	86,475
Level 2 \| Corporate bonds
Financial instruments and fair value measurements
Debt securities	$ 188,396	$ 196,603

Accrued expenses and other liabilities - Summary of accrued expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued expenses and other liabilities.
Payroll and bonuses	$ 6,496	$ 7,062
Interest		117
Accrued clinical trial related costs	470	314
Professional and legal fees	1,642	1,637
Operating lease liability, current	$ 1,513	$ 475
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Total accrued expenses and other liabilities	Total accrued expenses and other liabilities
Other	$ 28	$ 236
Total accrued expenses and other liabilities	$ 10,149	$ 9,841

Bristol-Myers Squibb Collaboration - Total transaction price (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Bristol-Myers Squibb Collaboration
Total	$ 115,753
Less current portion of deferred revenue	(4,372)	$ (7,154)
Total long-term deferred revenue	111,381	$ 110,834
Transaction price
Bristol-Myers Squibb Collaboration
Total	123,187
Total long-term deferred revenue	123,187
Cumulative collaboration revenue recognized
Bristol-Myers Squibb Collaboration
Cumulative collaboration revenue recognized	(7,434)
Total long-term deferred revenue	7,434
Option rights
Bristol-Myers Squibb Collaboration
Total	109,164
Option rights \| Transaction price
Bristol-Myers Squibb Collaboration
Total	109,164
Research and development services
Bristol-Myers Squibb Collaboration
Total	6,589
Research and development services \| Transaction price
Bristol-Myers Squibb Collaboration
Total	14,023
Research and development services \| Cumulative collaboration revenue recognized
Bristol-Myers Squibb Collaboration
Cumulative collaboration revenue recognized	$ (7,434)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Stock-based compensation - Reserved shares of common stock (Details) - 2021 Incentive Plan	Dec. 31, 2023 shares
Stock based compensation
Reserved shares of common stock for issuance	16,583,616
Options and RSUs
Stock based compensation
Options and RSUs issued and outstanding	12,436,131
Reserved shares of common stock for issuance	3,128,244
Employee stock purchase plan
Stock based compensation
Reserved shares of common stock for issuance	1,019,241

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Organization and description of the business - Going concern and liquidity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Organization and description of the business
Net Income (Loss)	$ (136,673)	$ (130,932)
Cash used in operations	(88,348)	$ 14,052
Amount of cash and cash equivalents on short and long term investments	$ 261,834

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Leases - Supplemental cash flow information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Supplemental cash flow information
Operating cash flows from operating leases	$ 9,434	$ (5,258)
Right-of-use assets obtained in exchange for lease obligations:		$ 19,599

Leases - Components of lease expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Amount of security deposits on certain leases	$ 413	$ 1,260
Impairment on right-of-use assets	4,943
Operating lease expense:
Fixed lease cost	5,755	4,803
Variable lease cost	1,403	1,261
Short term lease expense	906	2,600
Total operating lease expense	$ 8,064	$ 8,664
Minimum
Lessee, Lease, Description [Line Items]
Initial lease terms	5 years
Maximum
Lessee, Lease, Description [Line Items]
Initial lease terms	16 years

Long-term debt - Interest Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Long-term debt
Interest expense	$ 540	$ 787
Amortization of debt issuance costs, including end of term fee accretion	94	299
Interest expense	540	1,017
Accrued interest		117
Accrued expenses and other liabilities
Long-term debt
Accrued interest	$ 0	$ 117

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References + Details

Bristol-Myers Squibb Collaboration

12 Months Ended

Dec. 31, 2023

Bristol-Myers Squibb Collaboration

Bristol-Myers Squibb Collaboration

Note 9 – Bristol-Myers Squibb Collaboration

On January 7, 2022, the Company entered into the Collaboration Agreement with Bristol-Myers Squibb to collaborate on the research, development and commercialization of iNK and iT cell programs for hematologic malignancies and solid tumors (“Collaboration Program”, and each product candidate a “Development Candidate”). The Collaboration Agreement is within the scope of ASC 808, Collaborative Arrangements as both parties are active participants in the arrangement and are exposed to significant risks and rewards. While this arrangement is in the scope of ASC 808, the Company analogizes to ASC 606 for the accounting

for the Collaboration Agreement, including for the delivery of goods and services (i.e., units of account). Revenue recognized by analogizing to ASC 606 is recorded as collaboration revenue in the statements of operations.

Pursuant to the Collaboration Agreement, the Company and Bristol-Myers Squibb will initially collaborate on two Collaboration Programs focused on acute myeloid leukemia (“AML”) and multiple myeloma (“MM”), and Bristol-Myers Squibb has the option to add up to two additional Collaboration Programs for an additional fee. The Company is responsible for generating Development Candidates for each Collaboration Program, and Bristol-Myers Squibb has the option to elect to exclusively license the Development Candidates for pre-clinical development, clinical development and commercialization on a worldwide basis (“License Option”). Following Bristol-Myers Squibb’s exercise of the License Option, the Company will be responsible for performing IND-enabling studies, supporting Bristol-Myers Squibb’s preparation and submission of an IND, and manufacturing of clinical supplies until completion of a proof of concept clinical trial. Bristol-Myers Squibb will be responsible for all regulatory, clinical, manufacturing (after the proof of concept clinical trial) and commercialization activities for such Development Candidates worldwide. The Company has the option to co-promote Development Candidates generated from certain specified Collaboration Programs.

Under the terms of the Collaboration Agreement, Bristol-Myers Squibb made a non-refundable, upfront cash payment of $100,000 and will pay an exercise fee upon the exercise of the License Option (“Licensed Program” and product candidates developed under a Licensed Program, “Licensed Products”). For each Licensed Program, Bristol-Myers Squibb will pay up to $235,000 in milestone payments upon the first achievement of certain development and regulatory milestones and will pay up to $500,000 per Licensed Product in net sales-based milestone payments. Bristol-Myers Squibb will also pay the Company tiered royalties per Licensed Product as a percentage of net sales in the high-single digits to low-teens, subject to reduction for biosimilar competition, compulsory licensing and certain third party license costs. If Century exercises its co-promote option, such royalty percentage will be increased to low-teens to high-teens in respect of the sales of the co-promoted Licensed Products in the United States. The royalty term shall terminate on a Licensed Product-by-Licensed Product and country-by-country basis on the latest of (i) the twelve (12) year anniversary of the first commercial sale of such Licensed Product in such country, (ii) the expiration of any regulatory exclusivity period that covers such Licensed Product in such country, and (iii) the expiration of the last-to-expire licensed patent of the Company or a jointly owned patent that covers such the Licensed Product in such country. After expiration of the applicable royalty term for a Licensed Product in a country, all licenses granted by the Company to Bristol-Myers Squibb for such Licensed Product in such country will be fully paid-up, royalty-free, perpetual and irrevocable.

In connection with the Collaboration Agreement, Bristol-Myers Squibb purchased 2,160,760 shares of the Company’s common stock at a price per share of $23.14, for an aggregate purchase price of $50,000. In determining the fair value of the common stock issued to Bristol-Myers Squibb, the Company considered the closing price of the common stock on the date of the transaction and included a lack of marketability discount because the shares are subject to certain restrictions. The Company determined the common stock purchase represented a premium of $7.82 per share, or $23,187 in the aggregate (“Equity Premium”), and the remaining $26,813 was recorded as issuance of common stock in stockholders’ equity.

The Company identified the following commitments under the arrangement: (i) research and development services (“R&D Services”) under each of the two initial Collaboration Programs and (ii) Bristol-Myers Squibb’s License Option to elect to exclusively license the Development Candidates for each of the two initial Collaboration Programs. The Company determined that these four commitments represent distinct performance obligations for purposes of recognizing revenue and will recognize revenue as the Company fulfills each performance obligation.

The Company determined that the upfront payment and Equity Premium constitute the transaction price at the inception of the Collaboration Agreement. The future potential development and regulatory milestone payments were fully constrained at contract inception as the risk of significant revenue reversal related to these amounts has not yet been resolved. The achievement of the future potential milestones is not within the

Company’s control and is subject to certain research and development success and therefore carries significant uncertainty. The Company will reevaluate the likelihood of achieving these milestones at the end of each reporting period and adjust the transaction price in the period the risk is resolved. In addition, the Company will recognize any consideration related to sales-based milestones and royalties when the subsequent sales occur.

The total transaction price of $123,187 was allocated to the performance obligations based on their estimated standalone selling price on January 7, 2022. The stand-alone selling price of the research and development services was estimated using the expected cost-plus margin approach, and the stand-alone selling price of the License Options was based on a discounted cash flow approach and considered several factors including, but not limited to, discount rate, development timeline, regulatory risks, estimated market demand, and future revenue potential using an adjusted market approach. The allocated transaction price is recognized as revenue in one of two ways:

●

Research and development services: The Company recognizes the portion of the transaction price allocated to each of the research and development performance obligations as the research and development services are provided, using an inputs method, in proportion to costs incurred to date for each research development target as compared to total costs incurred and expected to be incurred in the future to satisfy the underlying obligation related to each research and development target. The transfer of control occurs over this period and, in management’s judgment, is the best measure of progress towards satisfying the performance obligation.

●

License option rights: The transaction price allocated to the license options rights, which are considered material rights to license and commercialize the underlying research and development target, are deferred until the period that Bristol-Myers Squibb elects to exercise or elects to not exercise its option or when the option to exercise expires.

The following table summarizes the allocation of the total transaction price to the identified performance obligations under the arrangement, and the amount of the transaction price unsatisfied as of December 31, 2023:


			Cumulative collaboration		Deferred
Performance obligations:	Transaction price		revenue recognized		collaboration revenue
Option rights	$	109,164	$	-	$	109,164
Research and development services		14,023		(7,434)		6,589
Total		123,187		(7,434)		115,753
Less current portion of deferred revenue		-		-		(4,372)
Total long-term deferred revenue	$	123,187	$	(7,434)	$	111,381

As a direct result of the execution of the Collaboration Agreement, the Company incurred $10,000 in fees to amend the FCDI agreement to gain access to the territory rights of Japan. This is recorded as in-process research and development expenses in the consolidated statement of operations and comprehensive loss for the year ended December 31, 2022.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Reduction in force (Details) - Employee Severance [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Reduction in force
Amount of cash-based expenses	$ 2,032
Amount of non-cash stock-based compensation charge	581
General and administrative
Reduction in force
Amount of employee severances, benefits and related costs	292
Amount of non-cash stock-based compensation charge	171
Research and development
Reduction in force
Amount of employee severances, benefits and related costs	1,740
Amount of non-cash stock-based compensation charge	$ 410

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Related party transactions

12 Months Ended

Dec. 31, 2023

Related party transactions

Related party transactions

Note 16—Related party transactions

License and Collaboration Agreements with Shareholder

The Company owns licenses and other contracts with FUJIFILM Cellular Dynamics, Inc. (“FCDI”). FCDI is a shareholder of Century. The acquired licenses and other contracts with FCDI are as follows:

FCDI Agreements

The Company owns a non-exclusive license agreement with FCDI. The license provides the Company with certain patents and know-how related to the reprogramming of human somatic cells to induce pluripotent stem cells (“iPSCs”) (“Reprogramming License Agreement”). Under this agreement, the Company is required to make certain developmental and regulatory milestone payments as well as royalty payments upon commercialization. Royalties are in the low single digits on the sale of all licensed products.

The Company also owns an exclusive license agreement with FCDI (“Differentiation Licenses Agreement”). The Differentiation Licenses Agreement provides the Company with patents and know-how related to human iPSC exclusively manufactured by FCDI.

In October 2019, the Company entered into the Collaboration Agreement with FCDI (“Collaboration Agreement”), whereby FCDI provides certain services to the Company to develop and manufacture iPSCs and immune cells derived therefrom. FCDI provides services in accordance with the approved research plan and related research budget. The initial research plan covered the period from October 2019 through March 31, 2022. In July, 2022 the Company amended the Collaboration Agreement to extend the term through September 30, 2025, and in September 2023, the Company amended the Collaboration Agreement in connection with the Autoimmune Licenses (as defined below).

In March 2021, the Company entered into a Manufacturing Agreement with FCDI, (“Manufacturing Agreement”), pursuant to which FCDI will provide certain agreed upon technology transfer, process development, analytical testing and cGMP manufacturing services to the Company.

In January 2022, the Company and FCDI entered into a letter agreement (the “Letter Agreement”), which amends the Reprogramming Licenses Agreement, Differentiation License Agreement and Manufacturing Agreement (the “FCDI Agreements”) pursuant to the Company’s Research Collaboration and License Agreement with Bristol-Myers Squibb. Pursuant to the Letter Agreement, and in consideration for amending the FCDI Agreements, the Company paid to FCDI an upfront payment of $10,000, and will pay FCDI (i) a percentage of any milestone payments received by the Company under the FCDI Collaboration Agreement in respect of achievement of development or regulatory milestones specific to Japan, and (ii) a percentage of all royalties received by the Company under the FCDI Collaboration Agreement in respect of sales of products in Japan.

In September 2023, the Company and FCDI entered into a worldwide license agreement whereby FCDI will grant non-exclusive licenses to the Company for certain patent rights and know-how related to cell differentiation and reprogramming for the development and commercialization of iPSC-derived therapies for the treatment of inflammatory and autoimmune diseases (the “Autoimmune license”). In addition, the Company and FCDI entered into an amendment to each of the Reprogramming license and the Differentiation License to expand the licenses related to the development and commercialization of IPSC-derived cancer immunotherapeutic to also include inflammatory and autoimmune diseases. Under the terms of these agreements, FCDI will be eligible to receive certain development and regulatory milestone payments as well as low single-digit royalties related to products developed in connection with such agreements. The Company recorded an upfront payment in the amount of $4,000 which is included as In-Process research and development. In addition, Century paid FCDI a $1,000 milestone fee pursuant to the Autoimmune License for filing of the IND for SLE for CNTY-101, which is also included in In-Process research and development in the consolidated statements of operations as of December 31, 2023.

During the years ended December 31, 2023 and 2022, the Company made payments of $5,200 and $15,100 and incurred research and development expenses of $0 and $4,900, in-process research and development expenses of $5,000 and $10,000 and legal fees of $200 and $200, respectively, related to the FCDI agreements. The legal fees are recorded within general and administrative expenses in the consolidated statements of operations and comprehensive loss.

Bayer Option Agreement

Bayer Health, LLC (“Bayer”), a shareholder in the Company, has the right of first refusal to acquire certain products researched and developed by the Company. Subject to certain exceptions, Bayer’s right of first refusal is exercisable with respect to up to four products and may only exercise these option rights in a non-sequential and alternating manner, and such rights are subject to additional limitations.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org//1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

+ Details

Summary of significant accounting policies and basis of presentation

12 Months Ended

Dec. 31, 2023

Summary of significant accounting policies and basis of presentation

Summary of significant accounting policies and basis of presentation

Note 2—Summary of significant accounting policies and basis of presentation

Basis of presentation

The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“US GAAP”), which contemplate the continued existence of the Company. Since commencing principal activities, the Company has been engaged primarily in research and development activities and raising capital.

Certain prior year information has been reclassified to conform to the fiscal year 2023 presentation.

Segment information

Operating segments are identified as components of an enterprise for which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions on how to allocate resources and assess performance. The Company views its operations and manages the business as one operating segment.

Use of estimates

The preparation of consolidated financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and reported amounts of expenses during the reporting period. Estimates and assumptions are primarily made in relation to the valuations supporting stock compensation, the estimation of the incremental borrowing rate for operating leases and standalone selling prices of performance obligations in collaboration agreements. If actual results differ from the Company’s estimates, or to the extent these estimates are adjusted in future periods, the Company’s results of operations could either benefit from, or be adversely affected by, any such change in estimate.

Concentration of credit risk and other risks and uncertainties

Financial instruments, which potentially subject the Company to significant concentrations of credit risk, consist of cash, cash equivalents, U.S. Treasury bills and bonds, as well as corporate bonds. Cash and cash equivalents, as well as short and long-term investments include a checking account and asset management accounts held by a limited number of financial institutions. At times, such deposits may be in excess of insured limits. As of December 31, 2023 and 2022, the Company has not experienced any losses on its deposits of cash and cash equivalents.

The Company’s future results of operations involve a number of risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, rapid technological change, uncertainty of market acceptance of its products, competition from substitute products and larger companies, protection of proprietary technology, strategic relationships, and dependence on key individuals.

Products developed by the Company require clearances from the U.S. Food and Drug Administration or other international regulatory agencies prior to commercial sales. There can be no assurance the Company’s future products will receive the necessary clearances. If the Company was denied clearance, clearance was delayed, or if the Company was unable to maintain clearance, it could have a material adverse impact on the Company.

Fair value of financial instruments

The Company discloses and recognizes the fair value of its assets and liabilities using a hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The hierarchy gives the highest priority to valuations based upon unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to valuations based upon unobservable inputs that are significant to the valuation (Level 3 measurements). The guidance establishes three levels of the fair value hierarchy as follows:

Level 1Inputs that reflect unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date;

Level 2Inputs other than quoted prices that are observable for the asset or liability either directly or indirectly, including inputs in markets that are not considered to be active;

Level 3Inputs are unobservable in which there is little or no market data available, which require the reporting entity to develop its own assumptions that are unobservable.

Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires management to make judgments and consider factors specific to the asset or liability.

Cash and cash equivalents

Management considers all highly liquid investments with an insignificant interest rate risk and original maturities of three months or less to be cash equivalents.

Restricted cash

As of December 31, 2023 and 2022, the Company had $1,979 in cash on deposit to secure certain lease commitments. Restricted cash is recorded separately in the Company’s consolidated balance sheets.

The following provides a reconciliation of the Company’s cash, cash equivalents, and restricted cash as reported in the consolidated balance sheets to the amounts reported in the consolidated statements of cash flows:


	December 31, 2023		December 31, 2022
Cash and cash equivalents	$	47,324	$	84,265
Restricted cash		1,979		1,979
Cash, cash equivalents, and restricted cash	$	49,303	$	86,244

Investments

The Company invests in fixed maturity securities including U.S. Treasury bills and bonds as well as corporate bonds. The investments are classified as available-for-sale and reported at fair value. Unrealized gains or losses are determined by comparing the fair market value of the securities with their cost or amortized cost. Realized gains and losses on investments are recorded on the trade date and are included in the statement of operations. Unrealized gains and losses on investments are recorded in other comprehensive loss on the consolidate statements of operations and comprehensive loss. The cost of securities sold is based on the specified identification method. Investment income is recognized as earned and discounts or premiums arising from the purchase of debt securities are recognized in investment income using the interest method over the remaining term of the security. Securities with an original maturity date greater than three months

that mature within one year of the balance sheet date are classified as short-term, while investments with a maturity date greater than one year are classified as long-term.

Property and equipment, net

Property and equipment are recorded at cost. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, which is generally five years. Leasehold improvements are amortized over the shorter of the asset’s useful life or the remaining term of the lease. Construction in progress includes direct cost related to the construction of leasehold improvements and is stated at original cost. Such costs are not depreciated until the asset is completed and placed into service. Once the asset is placed into service, these capitalized costs will be allocated to leasehold improvements and will be depreciated over the shorter of the asset’s useful life or the remaining term of the lease. Computer software and equipment includes implementation costs for cloud-based software and network equipment.

Expenditures for major additions and improvements are capitalized, while minor replacements, maintenance, and repairs are charged to expense as incurred. When property is retired or otherwise disposed of, the costs and accumulated depreciation are removed from the respective accounts, with any resulting gain or loss recognized concurrently.

Research and development expenses

Research and development expenses include costs directly attributable to the conduct of research and development programs, including the cost of salaries, payroll taxes, employee benefits, stock compensation, materials, supplies, rent, depreciation on and maintenance of research equipment with alternative future use, and the cost of services provided by outside contractors. All costs associated with research and development are expensed as incurred.

Clinical trial costs are a component of research and development expenses. The Company expenses costs for its clinical trial activities performed by third parties, including clinical research organizations and other service providers, as they are incurred, based upon estimates of the work completed over the life of the individual study in accordance with associated agreements. The Company uses information it receives from internal personnel and outside service providers to estimate the clinical trial costs incurred.

Stock-based compensation

Employees, consultants and members of the board of directors of the Company have received stock options and restricted stock of the Company. The Company recognizes the cost of the stock-based compensation incurred as its employees and board members vest in the awards. The Company accounts for stock-based compensation arrangements in accordance with provisions of Accounting Standards Codification (“ASC”) 718, Compensation—Stock Compensation. ASC 718 requires the recognition of compensation expense, using a fair-value based method, for costs related to all share-based payments including stock options. ASC 718 requires companies to estimate the fair value of share-based payment awards on the date of grant using an option-pricing model. The Company uses the Black-Scholes option-pricing model (“Black Scholes”) to determine the fair value of options granted. The Company’s stock-based awards are subject to service-based vesting conditions and performance-based vesting conditions. Compensation expense related to awards to employees and directors with service-based vesting conditions is recognized on a straight-line basis based on the grant date fair value over the associated service period of the award, which is generally the vesting term. For performance-based awards, the Company reassesses at each reporting date whether achievement of the performance condition is probable and accrues compensation expense if and when achievement of the performance condition is probable.

Black-Scholes requires inputs based on certain subjective assumptions, including (i) the expected stock price volatility, (ii) the expected term of the award, (iii) the risk-free interest rate and (iv) expected dividends. The historical volatility is calculated based on a period of time commensurate with expected term assumption.

The risk-free interest rate is based on U.S. Treasury securities with a maturity date commensurate with the expected term of the associated award. The expected dividend yield is assumed to be zero as the Company has never paid dividends and has no current plans to pay any dividends on its common stock. Forfeitures are recognized as they occur.

Warrants

The Company has issued warrants that have been recognized as equity, and the fair value is recorded into additional paid-in capital in the accompanying consolidated balance sheets. Warrants are accounted for in accordance with applicable accounting guidance provided in ASC Topic 815, Derivatives and Hedging—Contracts in Entity’s Own Equity, as either derivative liabilities or as equity instruments depending on the specific terms of the warrant agreement. The Company’s warrants issued are in connection with its long-term debt and in connection with services provided by consultants, and are equity classified on the accompanying consolidated balance sheets. Equity classified warrants are accounted for at fair value on the issuance date, using Black Scholes, with no changes in fair value recognized after the issuance date.

Foreign currency translation

The reporting currency of the Company is the U.S. dollar. The functional currency of Century Canada is the Canadian dollar. Assets and liabilities of Century Canada are translated into U.S. dollars based on exchange rates at the end of each reporting period. Expenses are translated at average exchange rates during the reporting period. Gains and losses arising from the translation of assets and liabilities are included as a component of accumulated other comprehensive loss or income on the Company’s consolidated balance sheets. Gains and losses resulting from foreign currency transactions are reflected within the Company’s consolidated statements of operations and comprehensive loss. The Company has not utilized any foreign currency hedging strategies to mitigate the effect of its foreign currency exposure.

Intercompany payables and receivables are considered to be long-term in nature and any change in balance due to foreign currency fluctuation is included as a component of the Company’s consolidated comprehensive loss and accumulated other comprehensive income (loss) within the Company’s consolidated balance sheets.

Basic and diluted net loss per common shares

Basic net loss per common share is computed by dividing net loss applicable to common shareholders by the weighted-average number of common shares outstanding during the period. The Company computes diluted net loss per common share by dividing the net loss applicable to common shareholders by the sum of the weighted-average number of common shares outstanding during the period plus the potential dilutive effects of its warrants, restricted stock and stock options to purchase common shares, but such items are excluded if their effect is anti-dilutive. Because the impact of these items are anti-dilutive during periods of net loss, there were no differences between the Company’s basic and diluted net loss per common share for the years ended December 31, 2023 and 2022.

Early exercised options

The Company allowed certain of its employees and its consultants to exercise options granted under the 2018 Plan (Note 15) prior to vesting and prior to its IPO. The shares related to early exercised stock options are subject to the Company’s repurchase right upon termination of employment or services at the lesser of the original purchase price or fair market value at the time of repurchase. In order to vest, the holders are required to provide continued service to the Company. The early exercise by an employee or consultant of a stock option is not considered to be a substantive exercise for accounting purposes, and therefore, the payment received by the employer for the exercise price is recognized as a liability. For accounting purposes, unvested early exercised shares are not considered issued and outstanding and therefore not reflected as issued and outstanding in the accompanying consolidated balance sheets or the consolidated statements of changes in stockholders’ equity until the awards vest. The deposits received are initially recorded in deposit

liability. The liabilities are reclassified to common stock and additional paid-in-capital as the repurchase right lapses. At December 31, 2023 and 2022, there was $640 and $1,584, respectively, recorded in deposit liability related to shares held by employees and nonemployees that were subject to repurchase.

All shares that were early exercised by the executives of the Company are considered legally issued, however, for accounting purposes, only vested shares are considered issued. Below is a reconciliation of shares issued and outstanding:


	December 31, 2023	December 31, 2022
Total shares legally outstanding	60,504,397	59,137,491
Less: unvested early exercised shares	(119,280)	(470,800)
Less: unvested restricted stock awards (Note 15)	(49,416)	(193,031)
Total shares issued and outstanding	60,335,701	58,473,660

Income Taxes

The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, the Company determines deferred tax assets and liabilities on the basis of the differences between the financial statement and tax bases of assets and liabilities by using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date.

The Company recognizes deferred tax assets to the extent that the Company believes that these assets are more likely than not to be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. If the Company determines that the Company would be able to realize our deferred tax assets in the future in excess of their net recorded amount, the Company would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes.

The Company records uncertain tax positions in accordance with ASC 740 on the basis of a two-step process in which (1) the Company determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, the Company recognizes the largest amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority.

The Company recognizes interest and penalties related to unrecognized tax benefits on the income tax expense line in the accompanying consolidated statement of operations. As of December 31, 2023, no accrued interest or penalties are included on the related tax liability line in the consolidated balance sheet.

Collaboration revenue

The Company may enter into collaboration and licensing agreements with strategic partners for research and development, manufacturing, and commercialization of its product candidates. Payments under these arrangements may include non-refundable, upfront fees; reimbursement of certain costs; customer option fees for additional goods or services; payments upon the achievement of development, regulatory, and commercial milestones; sales of product at certain agreed-upon amounts; and royalties on product sales.

The Company recognizes revenue in accordance with ASC Topic 606, Revenue from Contracts with Customers, or ASC 606. This standard applies to all contracts with customers. When an agreement falls under the scope of other standards, such as ASC Topic 808, Collaborative Arrangements, or ASC 808, the Company will apply the recognition, measurement, presentation, and disclosure guidance in ASC 606 to the

performance obligations in the agreements if those performance obligations are with a customer. Revenue recognized by analogizing to ASC 606 is recorded as collaboration revenue on the statements of operations.

Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. In determining the appropriate amount of revenue to be recognized as it fulfills its obligations under a collaboration agreement, the Company performs the following steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations on a relative stand-alone selling price basis; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation.

As part of the accounting for these arrangements, the Company must use its judgment to determine the stand-alone selling price for each performance obligation identified in the contract for the allocation of transaction price. The estimation of the stand-alone selling price may include such estimates as forecasted revenues and costs, development timelines, discount rates, and probabilities of regulatory and commercial success. The Company also applies significant judgment when evaluating whether contractual obligations represent distinct performance obligations, allocating transaction price to performance obligations within a contract, determining when performance obligations have been met, assessing the recognition and future reversal of variable consideration and determining and applying appropriate methods of measuring progress for performance obligations satisfied over time. Amounts expected to be recognized as revenue within the 12 months following the balance sheet date are classified as current deferred revenue. Amounts not expected to be recognized as revenue within the 12 months following the balance sheet date are classified as deferred revenue, non-current.

If an arrangement is determined to contain customer options that allow the customer to acquire additional goods or services, the goods and services underlying the customer options are not considered to be performance obligations at the outset of the arrangement, as they are contingent upon option exercise. The Company evaluates the customer options for material rights or options to acquire additional goods or services for free or at a discount. If the customer options are not determined to represent a material right, no transaction price is allocated to these options and the Company will account for these options at that time they are exercised. If the customer options are determined to represent a material right, the material right is recognized as a separate performance obligation at the outset of the arrangement.

The obligations under the Company’s collaboration agreements may include research and development services to be performed by the Company for or on behalf of the customer. Amounts allocated to these performance obligations are recognized as the Company performs these obligations, and revenue is measured based on an inputs method of costs incurred to date of budgeted costs. Under certain circumstances, the Company may be reimbursed for certain expenses incurred under the research and development services.

At the inception of each arrangement that includes development milestone payments, the Company evaluates whether the milestones are considered probable of being achieved and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company evaluates factors such as the scientific, clinical, regulatory, commercial and other risks that must be overcome to achieve the particular milestone in making this assessment. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. At the end of each subsequent reporting period, the Company reevaluates the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such

adjustments are recorded on a cumulative catch-up basis in the statements of operations in the period of adjustment.

Impairment of long-lived assets

The Company reviews its long-lived assets for impairment annually, or whenever events or circumstances indicate that the carrying amount of an asset may not be fully recoverable. The Company assesses the recoverability of these assets by comparing the carrying amount of such assets or asset group to the future undiscounted cash flows it expects the assets or asset group to generate. The Company recognizes an impairment loss if the sum of the expected long-term discounted cash flows that the long-lived asset is expected to generate is less than the carrying amount of the long-lived asset being evaluated. The Company analyzed its long-lived assets for impairment and recorded a $16,365 impairment charge related to property and equipment and its right-of-use assets in its consolidated statements of operations and comprehensive loss for the year ended December 31, 2023.

Recent accounting pronouncements

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses of Financial Instruments (ASC 326). The guidance is effective for the Company beginning January 1, 2023 and it changes how entities account for credit losses on the financial assets and other instruments that are not measured at fair value through net income, including available-for-sale debt securities. The adoption of ASC 326 did not have a material impact on the consolidated financial statements.

In December 2023, the FASB issued ASU No. 2023-09, "Income Taxes (Topic 740): Improvements to Income Tax Disclosures ("ASU 2023-09")." ASU 2023-09 requires entities to provide additional information in their tax rate reconciliation and additional disclosures about income taxes paid by jurisdiction. ASU 2023-09 is effective for annual reporting periods beginning after December 15, 2024, with early adoption permitted. The guidance should be applied prospectively, but entities have the option to apply it retrospectively for each period presented. The Company is currently evaluating the impact of adopting this new accounting guidance.

Long-term debt (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Long-term debt
Principal	$ 10,000
Plus: End of term fee	395
Less: Debt discount attributable to warrants, net of accretion	(8)
Less: Unamortized deferred financing cost and end of term fee, net of accretion	(146)
Long-term debt, net	$ 10,241

Income taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income taxes

Schedule of income (loss) before provision for income taxes


		Year Ended December 31,
	2023		2022
Domestic	$	(135,003)	$	(131,314)
Foreign		211		473
Loss before provision for income taxes	$	(134,792)	$	(130,841)

Schedule of components of the provision for income taxes


		Year Ended December 31,
	2023		2022
Current expense:
Federal	$	418	$	-
State		1,267		-
Foreign		199		86
Total current expense:		1,884		86

Deferred expense:
Federal		-		-
State		-		-
Foreign		(3)		5
Total deferred expense:		(3)		5

Total income tax expense	$	1,881	$	91

Schedule of reconciliation of Company's statutory income tax rate to the Company's effective income tax rate


		Year Ended December 31,
	2023		2022
Income at US statutory rate		21.0%		21.0%
State taxes, net of federal benefit		8.7%		11.0%
Permanent differences		0.0%		0.6%
Tax credits		3.7%		1.9%
Tax law change		0.0%		0.0%
Foreign rate differential		0.0%		0.0%
Valuation allowance		(36.3)%		(33.8)%
Other		1.6%		(0.7)%
		(1.3)%		0.0%

Schedule of deferred income tax assets and liabilities


		Year Ended December 31,
	2023		2022
Deferred Tax Assets
Net operating loss carryforwards	$	31,092	$	35,187
Lease liability		11,273		12,236
Accrued expenses & other		-		605
Deferred revenue		36,013		-
Credits		11,596		5,351
Capitalized R&D expenses		36,861		28,693
Stock based compensation		7,031		3,391
Amortization		3,974		4,304
Total deferred tax assets		137,840		89,767
Valuation allowance		(127,452)		(78,469)
Net deferred tax assets		10,388		11,298
Deferred tax liability
Depreciation		(3,988)		(2,264)
Right-of-use asset		(6,332)		(9,039)
Net unrealized losses		(68)		-
Total deferred tax liabilities		(10,388)		(11,303)
Net deferred tax liability	$	-	$	(5)

As of December 31, 2023, the Company recorded income tax expense of $1,881, which includes a tax provision of $199 related to its income tax obligations of its Canada operations. The Company has taxable income for tax year 2023, due primarily to revenue recognition for tax purposes from the Company's Research Collaboration and License Agreement entered into with Bristol-Myers Squibb in 2022.

As of December 31, 2023, the Company had an indefinite-lived federal net operating loss carryforward of $92,896. As of December 31, 2023, the Company has state and local NOL carryforwards of $106,002 and $124,838, respectively. The state and local net operating loss carryforwards begin to expire in 2024.

As of December 31, 2023, the Company also has federal tax credits of $11,596, which begin to expire in 2039.

Future realization of the tax benefits of existing temporary differences and net operating loss carryforwards ultimately depends on the existence of sufficient taxable income within the carryforward period. As of December 31, 2023 and 2022, the Company performed an evaluation to determine whether a valuation allowance was needed. The Company considered all available evidence, both positive and negative, which included the results of operations for the current and preceding years. The Company determined that it was not possible to reasonably quantify future taxable income and determined that it is more likely than not that all of the deferred tax assets will not be realized. Accordingly, the Company maintained a full valuation allowance against its net deferred tax asset as of December 31, 2023 and 2022.

Under Internal Revenue Code Section 382, if a corporation undergoes an “ownership change,” the corporation’s ability to use its pre-change NOL carryforwards and other pre-change tax attributes to offset its post-change income may be limited. We completed a study to assess whether an “ownership change” has occurred or whether there have been multiple ownership changes since we became a “loss corporation” as defined in Section 382. The study concluded an ownership change occurred in February, 2021. However, all limited NOLs and credits are available for use by the Company as of December 31, 2023. Future changes in our stock ownership, which may be outside of our control, may trigger an “ownership change.” In addition, future equity offerings or acquisitions that have equity as a component of the purchase price could result in an “ownership change.” If an “ownership change” has occurred or does occur in the future, utilization of the NOL carryforwards or other tax attributes may be limited, which could potentially result in increased future tax liability to the Company.

The Tax Cuts and Jobs Act (TCJA) resulted in significant changes to the treatment of research and developmental (R&D) expenditures under Section 174 of the IRC. For tax years beginning after December 31, 2021, taxpayers are required to capitalize and amortize all R&D expenditures that are paid or incurred in connection with their trade or business. Specifically, costs for U.S.-based R&D activities must be amortized over five years and costs for foreign R&D activities must be amortized over 15 years—both using a midyear convention. As of December 31, 2023, the Company capitalized a substantial amount of R&D expenditures primarily related to research and development activities that is subject to the amortization for tax purposes.

The calculation of the Company's tax liabilities involves dealing with uncertainties in the application of complex tax laws and regulations for both federal taxes and the many states in which we operate or do business in. ASC 740 states that a tax benefit from an uncertain tax position may be recognized when it is more likely than not that the position will be sustained upon examination, including resolutions of any related appeals or litigation processes, on the basis of the technical merits.

We record uncertain tax positions as liabilities in accordance with ASC 740 and adjust these liabilities when our judgment changes as a result of the evaluation of new information not previously available. Because of the complexity of some of these uncertainties, the ultimate resolution may result in a payment that is materially different from our current estimate of the unrecognized tax benefit liabilities. These differences will be reflected as increases or decreases to income tax expense in the period in which new information is available. As of December 31, 2023 and 2022 we have not recorded any uncertain tax positions in our financial statements.

We recognize interest and penalties related to unrecognized tax benefits on the income tax expense line in the accompanying consolidated statement of operations. As of December 31, 2023 and 2022, no accrued interest or penalties are included on the related tax liability line in the consolidated balance sheet.

The Company files tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending tax examinations. The Company's tax years are still open under statute from December 31, 2020, to the present. The resolution of tax matters is not expected to have a material effect on the Company's consolidated financial statements.

Stock-based compensation - Common stock available under 2021 Incentive Plan (Details) - shares		12 Months Ended
	Jan. 01, 2022	Dec. 31, 2023
Employee Stock Option [Member]
Stock based compensation
Options granted		(5,180,052)
Restricted stock units
Stock based compensation
RSU's granted		(3,908,729)
2021 Incentive Plan
Stock based compensation
Beginning balance		5,786,358
Shares reserved for issuance	2,750,276	2,954,788
Options and RSUs forfeited / cancelled		3,475,879
Ending balance		3,128,244
2021 Incentive Plan \| Employee Stock Option [Member]
Stock based compensation
Options granted		(5,180,052)
2021 Incentive Plan \| Restricted stock units
Stock based compensation
RSU's granted		(3,908,729)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Reduction in force

12 Months Ended

Dec. 31, 2023

Reduction in force

Reduction in force

Note 3 – Reduction in force

During the year ended December 31, 2023, the Company incurred $2,032 of cash-based expenses related to employee severances, benefits and related costs. Of these amounts, $292 related to G&A expense, while $1,740 related to R&D expense. In addition, the Company recorded non-cash stock-based compensation charge of $581 related to modification of equity awards for employees impacted by the restructuring during the year ended December 31, 2023. Of these amounts, $171 related to G&A expense, while $410 related to R&D expense. There were no remaining outstanding liabilities related to the reduction in force at December 31, 2023.

Prepaid expenses and other current assets

12 Months Ended

Dec. 31, 2023

Prepaid expenses and other current assets.

Prepaid expenses and other current assets

Note 5—Prepaid expenses and other current assets

The following is a summary of prepaid expenses and other current assets:


	December 31, 2023		December 31, 2022
Research and development	$	34	$	110
Insurance		761		1,454
Software licenses and other		1,011		1,417
Income tax receivable		650		—
Reimbursement receivable		15		780
Warranties		215		242
Accrued interest receivable		1,570		—
Total prepaid expenses and other current assets	$	4,256	$	4,003

Summary of significant accounting policies and basis of presentation (Tables)

12 Months Ended

Dec. 31, 2023

Summary of significant accounting policies and basis of presentation

Schedule of reconciliation of the Company's cash, cash equivalents, and restricted cash


	December 31, 2023		December 31, 2022
Cash and cash equivalents	$	47,324	$	84,265
Restricted cash		1,979		1,979
Cash, cash equivalents, and restricted cash	$	49,303	$	86,244

Reconciliation of shares issued and outstanding


	December 31, 2023	December 31, 2022
Total shares legally outstanding	60,504,397	59,137,491
Less: unvested early exercised shares	(119,280)	(470,800)
Less: unvested restricted stock awards (Note 15)	(49,416)	(193,031)
Total shares issued and outstanding	60,335,701	58,473,660

Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases

Schedule of components of lease expenses


	For the		For the
	Year Ended		Year Ended
	December 31, 2023		December 31, 2022
Operating lease expense:
Fixed lease cost	$	5,755	$	4,803
Variable lease cost		1,403		1,261
Short term lease expense		906		2,600
Total operating lease expense	$	8,064	$	8,664

Schedule of Supplemental Balance Sheet Information related to leases


		As of		As of
		December 31,		December 31,
	Location in Balance Sheet	2023		2022

Operating lease right-of-use asset, net	Operating lease right-of-use assets	$	20,376	$	28,945
Operating lease liability, current	Accrued expenses and other liabilities	$	1,513	$	475
Operating lease liability, long-term	Operating lease liability, long-term		46,658		38,698
Total operating lease liability		$	48,171	$	39,173

Schedule of supplemental lease term and discount rate information related to leases


	As of December 31, 2023		As of December 31, 2022
Weighted-average remaining lease terms - operating leases	7.6 years		9.4 years
Weighted-average discount rate - operating leases	9.9	%	9.0	%

Schedule of supplemental cash flow information related to leases


	For the Year Ended		For the Year Ended
	December 31, 2023		December 31, 2022
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$	9,434	$	5,258
Right-of-use assets obtained in exchange for lease obligations:	$	—	$	19,599

Schedule of Future minimum lease payments of operating leases


	Operating Leases
2024	$	7,811
2025		8,656
2026		8,157
2027		8,342
2028		8,533
Thereafter		44,098
Total lease payments		85,597
Less: Imputed interest		(29,121)
Less: Tenant incentive receivable		(8,305)
Total	$	48,171

Stock-based compensation - Restricted stock (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Shares
Total Unvested	193,031
Total Unvested	49,416
Weighted Average Exercise Price
Deposit liability	$ 584,000	$ 866,000
Restricted stock
Shares
Total Unvested	193,031
Forfeited	(47,738)
Vested	(95,877)
Total Unvested	49,416
Weighted Average Exercise Price
Total Unvested	$ 8.41
Vested	2.50
Total Unvested	$ 7.27
Restricted stock vesting period	4 years
Unvested restricted stock with time-based vesting
Weighted Average Exercise Price
Unrecognized compensation expense	$ 311,000
Unrecognized compensation expense expected to be recognized over a weighted average period	1 year 2 months 19 days
Restricted stock vesting period	1 year 5 months 23 days
Deposit liability	$ 640	$ 1,589
Restricted stock units
Shares
Granted	3,908,729
Forfeited	(187,258)
Total Unvested	3,721,471
Weighted Average Exercise Price
Granted	$ 2.86
Forfeited	4.05
Total Unvested	$ 2.69
Unrecognized compensation expense	$ 6,405,000

Summary of significant accounting policies and basis of presentation - Impairment of Long-Lived Assets (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Summary of significant accounting policies and basis of presentation
Impairment	$ 16,365

Leases

12 Months Ended

Dec. 31, 2023

Leases

Leases

Note 11—Leases

The Company has commitments under operating leases for certain facilities used in its operations. The Company maintains security deposits on certain leases in the amounts of $413 and $1,260 within security deposits in its consolidated balance sheets at December 31, 2023 and 2022, respectively. The Company’s leases have initial lease terms ranging from 5 to 16 years. Certain lease agreements contain provisions for future rent increases. Variable lease costs generally include common area maintenance and real estate taxes.

The following table reflects the components of lease expense:


	For the		For the
	Year Ended		Year Ended
	December 31, 2023		December 31, 2022
Operating lease expense:
Fixed lease cost	$	5,755	$	4,803
Variable lease cost		1,403		1,261
Short term lease expense		906		2,600
Total operating lease expense	$	8,064	$	8,664

The following table reflects supplemental balance sheet information related to leases:


		As of		As of
		December 31,		December 31,
	Location in Balance Sheet	2023		2022

Operating lease right-of-use asset, net	Operating lease right-of-use assets	$	20,376	$	28,945
Operating lease liability, current	Accrued expenses and other liabilities	$	1,513	$	475
Operating lease liability, long-term	Operating lease liability, long-term		46,658		38,698
Total operating lease liability		$	48,171	$	39,173

The following table reflects supplement lease term and discount rate information related to leases:


	As of December 31, 2023		As of December 31, 2022
Weighted-average remaining lease terms - operating leases	7.6 years		9.4 years
Weighted-average discount rate - operating leases	9.9	%	9.0	%

The following table reflects supplemental cash flow information related to leases as of the periods indicated:


	For the Year Ended		For the Year Ended
	December 31, 2023		December 31, 2022
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases	$	9,434	$	5,258
Right-of-use assets obtained in exchange for lease obligations:	$	—	$	19,599

The following table reflects future minimum lease payments under noncancelable leases as of December 31, 2023:


	Operating Leases
2024	$	7,811
2025		8,656
2026		8,157
2027		8,342
2028		8,533
Thereafter		44,098
Total lease payments		85,597
Less: Imputed interest		(29,121)
Less: Tenant incentive receivable		(8,305)
Total	$	48,171

During the year ended December 31, 2023, the Company recognized $4,943 in impairment on right-of-use assets. See footnote 17, “Impairment on Long-Lived Assets”.

Summary of significant accounting policies and basis of presentation - Income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Summary of significant accounting policies and basis of presentation
Provisions or liability for income taxes	$ 1,884	$ 86
Accrued interest or penalties on unrecognized tax benefits	$ 0	$ 0

Leases - Operating lease - Other information (Details)	Dec. 31, 2023	Dec. 31, 2022
Leases
Weighted-average remaining lease terms (years) - operating leases	7 years 7 months 6 days	9 years 4 months 24 days
Weighted-average discount rate - operating leases	9.90%	9.00%

Stock-based compensation - Stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Weighted Average Remaining Contractual Term (years)
Outstanding	6 years 10 months 20 days	7 years 10 months 2 days
Exercisable	5 years 7 months 28 days
Aggregate Intrinsic Value
Outstanding, beginning	$ 8,991
Outstanding, ending	3,911	$ 8,991
Exercisable	$ 2,923
Employee Stock Option [Member]
Shares
Outstanding, beginning (in shares)	7,489,678
Granted	5,180,052
Exercised	(666,449)
Forfeited	(3,154,439)
Cancelled	(134,182)
Outstanding, ending (in shares)	8,714,660	7,489,678
Exercisable	3,938,006
Weighted Average Exercise Price
Outstanding, beginning	$ 7.77
Granted	4.05
Exercised	1.01
Forfeited	7.05
Cancelled	12.49
Outstanding, ending	6.24	$ 7.77
Exercisable	7.11
Weighted Average Remaining Contractual Term (years)
Weighted average grant date fair value	$ 2.82
Aggregate Intrinsic Value
Exercisable	$ 2,923	$ 6,864
Time Based Vesting
Weighted Average Remaining Contractual Term (years)
Unrecognized compensation expense	$ 17,566
Unrecognized compensation expense expected to be recognized over a weighted average period	2 years 10 months 6 days

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 47,324	$ 84,265
Short-term investments	125,414	231,233
Escrow deposits, current		220
Prepaid expenses and other current assets	4,256	4,003
Total current assets	176,994	319,721
Property and equipment, net	71,705	82,785
Operating lease right-of-use assets	20,376	28,945
Restricted cash	1,979	1,979
Long-term investments	89,096	51,854
Security deposits and non-current assets	541	1,260
Total assets	360,691	486,544
Current liabilities
Accounts payable	2,741	5,454
Accrued expenses and other liabilities	10,149	9,841
Deposit liability	584	866
Long-term debt, current		6,502
Deferred revenue, current	4,372	7,154
Total current liabilities	17,846	29,817
Operating lease liability, long term	46,658	38,698
Deposit liability, non-current	56	718
Deferred revenue, non-current	111,381	110,834
Long-term debt, net		3,739
Total liabilities	175,941	183,806
Commitments and contingencies (Note 10)
Stockholders' equity:
Preferred stock, $ 0.0001 par value, 10,000,000 shares authorized and 0 shares issued and outstanding at December 31, 2023 and December 31, 2022
Common stock, $0.0001 par value, 125,236,190 shares authorized; 60,335,701 and 58,473,660 shares issued and outstanding at December 31, 2023 and December 31, 2022, respectively	6	6
Additional paid-in capital	840,407	824,292
Accumulated deficit	(655,771)	(519,098)
Accumulated other comprehensive loss	108	(2,462)
Total stockholders' equity	184,750	302,738
Total liabilities and stockholders' equity	$ 360,691	$ 486,544

Income taxes

12 Months Ended

Dec. 31, 2023

Income taxes

Income taxes

Note 12—Income taxes

Until February 25, 2021, the Company was organized as a limited liability company, which is considered a passthrough entity for federal and state income tax purposes. As such, any taxable income or loss realized by the Company for the period ended February 25, 2021 was allocated to the members in accordance with their respective membership interest and reported on their individual tax returns.

Loss before provision for income taxes consisted of the following:


		Year Ended December 31,
	2023		2022
Domestic	$	(135,003)	$	(131,314)
Foreign		211		473
Loss before provision for income taxes	$	(134,792)	$	(130,841)

The components of the provision for income taxes is as follows:


		Year Ended December 31,
	2023		2022
Current expense:
Federal	$	418	$	-
State		1,267		-
Foreign		199		86
Total current expense:		1,884		86

Deferred expense:
Federal		-		-
State		-		-
Foreign		(3)		5
Total deferred expense:		(3)		5

Total income tax expense	$	1,881	$	91

A reconciliation of the Company's statutory income tax rate to the Company’s effective income tax rate is as follows:


		Year Ended December 31,
	2023		2022
Income at US statutory rate		21.0%		21.0%
State taxes, net of federal benefit		8.7%		11.0%
Permanent differences		0.0%		0.6%
Tax credits		3.7%		1.9%
Tax law change		0.0%		0.0%
Foreign rate differential		0.0%		0.0%
Valuation allowance		(36.3)%		(33.8)%
Other		1.6%		(0.7)%
		(1.3)%		0.0%

The net deferred income tax liability balance related to the following:


		Year Ended December 31,
	2023		2022
Deferred Tax Assets
Net operating loss carryforwards	$	31,092	$	35,187
Lease liability		11,273		12,236
Accrued expenses & other		-		605
Deferred revenue		36,013		-
Credits		11,596		5,351
Capitalized R&D expenses		36,861		28,693
Stock based compensation		7,031		3,391
Amortization		3,974		4,304
Total deferred tax assets		137,840		89,767
Valuation allowance		(127,452)		(78,469)
Net deferred tax assets		10,388		11,298
Deferred tax liability
Depreciation		(3,988)		(2,264)
Right-of-use asset		(6,332)		(9,039)
Net unrealized losses		(68)		-
Total deferred tax liabilities		(10,388)		(11,303)
Net deferred tax liability	$	-	$	(5)

As of December 31, 2023, the Company also has federal tax credits of $11,596, which begin to expire in 2039.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Related party transactions (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Jan. 07, 2022
Related party transactions
Accounts payable		$ 2,741	$ 5,454
Accrued expenses		28	236
Collaboration Agreement
Related party transactions
Upfront cash payment receivable				$ 100,000
FCDI Collaboration Agreement
Related party transactions
Payment to related party		5,200	15,100
Research and development		0	4,900
Legal fees		200	200
FCDI Collaboration Agreement \| In-process research and development expense
Related party transactions
Research and development		$ 5,000	$ 10,000
FCDI Collaboration Agreement \| Collaboration Agreement
Related party transactions
Upfront cash payment receivable				$ 10
Upfront payment made	$ 4,000
Milestone Fees	$ 1,000

Income taxes - Net deferred income tax asset (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred Tax Assets
Net operating loss carryforwards	$ 31,092	$ 35,187
Lease Liability	11,273	12,236
Accrued Expenses & Other		605
Deferred revenue	36,013
Credits	11,596	5,351
Research & Development (R&D) tax credits	36,861	28,693
Stock Compensation	7,031	3,391
Amortization	3,974	4,304
Total deferred tax assets	137,840	89,767
Valuation allowance	(127,452)	(78,469)
Net deferred tax assets	10,388	11,298
Deferred Tax Liability
Depreciation	(3,988)	(2,264)
ROU Asset	(6,332)	(9,039)
Net unrealized losses	(68)
Total deferred tax liabilities	$ (10,388)	(11,303)
Net deferred tax (liability)		$ (5)

Summary of significant accounting policies and basis of presentation (Policies)

12 Months Ended

Dec. 31, 2023

Summary of significant accounting policies and basis of presentation

Basis of presentation

Basis of presentation

Certain prior year information has been reclassified to conform to the fiscal year 2023 presentation.

Segment information

Segment information

Use of estimates

Use of estimates

Concentration of credit risk and other risks and uncertainties

Concentration of credit risk and other risks and uncertainties

Fair value of financial instruments

Cash and cash equivalents

Cash and cash equivalents

Management considers all highly liquid investments with an insignificant interest rate risk and original maturities of three months or less to be cash equivalents.

Restricted cash

Restricted cash

As of December 31, 2023 and 2022, the Company had $1,979 in cash on deposit to secure certain lease commitments. Restricted cash is recorded separately in the Company’s consolidated balance sheets.


	December 31, 2023		December 31, 2022
Cash and cash equivalents	$	47,324	$	84,265
Restricted cash		1,979		1,979
Cash, cash equivalents, and restricted cash	$	49,303	$	86,244

Investments

Investments

that mature within one year of the balance sheet date are classified as short-term, while investments with a maturity date greater than one year are classified as long-term.

Property and equipment, net

Property and equipment, net

Research and development expenses

Research and development expenses

Stock-based compensation

Stock-based compensation

Warrants

Warrants

Foreign currency translation

Foreign currency translation

Basic and diluted net loss per common shares

Basic and diluted net loss per common shares

Early exercised options


	December 31, 2023	December 31, 2022
Total shares legally outstanding	60,504,397	59,137,491
Less: unvested early exercised shares	(119,280)	(470,800)
Less: unvested restricted stock awards (Note 15)	(49,416)	(193,031)
Total shares issued and outstanding	60,335,701	58,473,660

Income taxes

Income Taxes

Collaboration revenue

Collaboration revenue

adjustments are recorded on a cumulative catch-up basis in the statements of operations in the period of adjustment.

Recent accounting pronouncements

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities
Net loss	$ (136,673)	$ (130,932)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	13,044	8,440
Amortization of deferred financing cost	94	299
Non-cash operating lease expense	(1,196)	1,631
Stock based compensation	14,622	10,669
Impairment	16,365
Amortization/accretion of investments	(3,984)
Change in operating assets and liabilities:
Escrow deposit	220	502
Prepaid expenses and other assets	667	1,028
Operating lease liability	13,819	5,258
Deferred revenue	(2,235)	117,988
Accounts payable	(2,361)	(4,788)
Accrued expenses and other liabilities	(730)	3,957
Net cash (used in) provided by operating activities	(88,348)	14,052
Cash flows from investing activities
Acquisition of property and equipment	(13,736)	(30,604)
Acquisition of fixed maturity securities, available for sale	(209,034)	(254,000)
Sale of fixed maturity securities, available for sale	283,902	271,476
Net cash provided by (used in) investing activities	61,132	(13,128)
Cash flows from financing activities
Proceeds from issuance of common stock and ESPP	516	345
Payments on long term debt	(10,241)
Proceeds from issuance of shares to collaboration partner		26,813
Net cash (used in) provided by financing activities	(9,725)	27,158
Net (decrease) increase in cash, cash equivalents, and restricted cash	(36,941)	28,082
Cash, cash equivalents and restricted cash, beginning of period	86,244	58,162
Cash, cash equivalents and restricted cash, end of period	49,303	86,244
Supplemental disclosure of cash and non-cash operating activities:
Cash paid for interest	586	1,097
Cash paid for income tax	2,521
Supplemental disclosure of non-cash investing and financing activities:
Purchase of property and equipment, accrued and unpaid	$ 352	$ 2,654

Income taxes - Operating loss carryforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit)	$ 1,881	$ 91
Tax credits	11,596
Accrued interest or penalties on unrecognized tax benefits	0	$ 0
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	92,896
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	106,002
Local
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	124,838
Canada Revenue Agency
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit)	$ 199

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS
Collaboration revenue	$ 2,235	$ 5,199
Operating expenses
Research and development	92,710	97,173
General and administrative	34,706	31,857
In-process research and development	5,000	10,000
Impairment of long-lived assets	16,365
Total operating expenses	148,781	139,030
Loss from operations	(146,546)	(133,831)
Interest expense	(540)	(1,430)
Interest income	12,677	4,420
Other expense	(383)
Total other income (expense)	11,754	2,990
Loss before provision for income taxes	(134,792)	(130,841)
Provision for income taxes	(1,881)	(91)
Net loss	$ (136,673)	$ (130,932)
Net loss per common share Basic (in dollars per share)	$ (2.30)	$ (2.27)
Net loss per common share Diluted (in dollars per share)	$ (2.27)	$ (2.96)
Weighted average common shares outstanding Basic (in shares)	59,314,389	57,755,842
Weighted average common shares outstanding Diluted (in shares)	57,755,842	32,392,554
Other comprehensive loss
Net Income (Loss)	$ (136,673)	$ (130,932)
Unrealized gain (loss) on investments	2,602	(1,786)
Foreign currency translation gain (loss)	(32)	(26)
Comprehensive loss	$ (134,103)	$ (132,744)

Basic and diluted net loss per common share (Tables)

12 Months Ended

Dec. 31, 2023

Basic and diluted net loss per common share

Schedule of basic and diluted net loss per shares of common stock


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
Numerator
Net loss	$	(136,673)	$	(130,932)

Denominator
Weighted-average common shares for basic and diluted net loss per share		59,314,389		57,755,842

Basic and diluted net loss per common share	$	(2.30)	$	(2.27)

Schedule of potential shares of common stock excluded


	Year Ended	Year Ended
	December 31,	December 31,
	2023	2022
Stock options to purchase common stock	8,714,660	7,489,678
Early exercised stock options subject to future vesting	119,280	470,800
Restricted stock award subject to future vesting	49,416	193,031
Unvested restricted stock units	3,721,471	—
Warrants	32,009	32,009
Total	12,636,836	8,185,518

Stock-based compensation

12 Months Ended

Dec. 31, 2023

Stock-based compensation

Stock-based compensation

Note 15—Stock-based compensation

On June 17, 2021, the Company adopted the Century Therapeutics, Inc. 2021 Equity Incentive Plan (the “2021 Incentive Plan”) which superseded the 2018 Incentive Plan and from that date forward all issuances of incentive awards will be governed by the 2021 Incentive Plan.

The 2021 Incentive Plan provides for the Company to sell or issue common stock or restricted common stock, restricted stock units (“RSUs”), or to grant incentive stock options or nonqualified stock options for the purchase of common stock, to employees, members of the board of directors, and consultants of the Company under terms and provisions established by the board of directors. Under the terms of the 2021 Incentive Plan, options may be granted at an exercise price not less than fair market value.

Upon adoption of the 2021 Incentive Plan, the Company was authorized to issue 5,481,735 shares of Common Stock under the 2021 Incentive Plan (which represents 5,640,711 shares of Common Stock initially available for grant under the 2021 Incentive Plan less 158,976 shares of Common Stock reserved for issuance upon the exercise of previously granted stock options that remain outstanding under the 2018 Incentive Plan). The number of shares of common stock initially reserved for issuance under the 2021 Incentive Plan shall be increased, upon approval by the board of directors, on January 1, 2022 and each January 1 thereafter, in an amount equal to the least of, (i) five percent (5%) of the outstanding common stock on the immediately preceding December 31, or (ii) such number of common stock determined by the board of directors no later than the immediately preceding December 31. For 2022, the 2021 Incentive Plan reserved shares were increased under clause (i) by 2,750,276 shares, effective as of January 1, 2022. For 2023, the 2021 Incentive Plan reserved shares were increased under clause (i) by 2,954,788 shares, effective as of January 1, 2023. As of December 31, 2023, there were 3,124,544 shares available for issuance under the 2021 Incentive Plan. In January 2024, common shares reserved for issuance under the 2021 Incentive Plan increased by 3,025,220 shares.

The Company’s stock-based awards are subject to service-based vesting conditions. Compensation expense related to awards to employees and directors with service-based vesting conditions is recognized on a straight-line basis based on the grant date fair value over the associated service period of the award, which is generally the vesting term. Stock awards granted typically vest over a four-year period but may be granted with different vesting terms. The Company may also issue awards with performance-based vesting conditions. For performance-based awards, the Company would reassess at each reporting date whether achievement of the performance condition is probable and accrue compensation expense if and when the achievement of the performance condition is probable. During the quarter ended June 30, 2023, the Company issued performance based RSUs that represent a contingent right to receive one share of the Company’s common stock. The RSUs shall vest 50% on November 1, 2023, with the remaining 50% vesting upon the earlier of: (i) November 1, 2024; and (ii) satisfaction of certain performance criteria. The Company is currently recording expense for these RSUs on the straight-line basis.

The Company recognizes the costs of the stock-based payments as the employees vest in the awards.

As of December 31, 2023, the Company had reserved shares of common stock for issuance as follows:


		Shares
Options and RSUs issued and outstanding		12,436,131
Shares available for future stock option and RSU grants		3,128,244
Shares available for employee stock purchase plan		1,019,241
Total		16,583,616

The shares of Common Stock available under the 2021 Incentive Plan as of December 31, 2023 are as follows:


		Shares
Balance, December 31, 2022		5,786,358
Shares reserved for issuance		2,954,788
Options granted		(5,180,052)
RSU’s granted		(3,908,729)
Options and RSUs forfeited / cancelled		3,475,879
Balance December 31, 2023		3,128,244

Stock Options

The following table summarizes stock option activity for the year ended December 31, 2023:


		Weighted Average
				Remaining		Aggregate
				Contractual		Intrinsic
				Term		Value
	Shares	Exercise Price		(years)		(in thousands)
Outstanding January 1, 2023	7,489,678	$	7.77	7.84	$	8,991
Granted	5,180,052		4.05	—		—
Exercised	(666,449)		1.01	—		—
Forfeited	(3,154,439)		7.05	—		—
Cancelled	(134,182)		12.49	—		—
Outstanding, December 31, 2023	8,714,660	$	6.24	6.89	$	3,911
Exercisable at December 31, 2023	3,938,006	$	7.11	5.66	$	2,923

The weighted average grant date fair value of awards for options granted during the period ended December 31, 2023 was $2.82. As of December 31, 2023, there was $17,566 of total unrecognized compensation expense related to unvested stock options with time-based vesting terms, which is expected to be recognized over a weighted average period of 2.57 years. The aggregate intrinsic value of options vested and exercisable as of December 31, 2023 and 2022 is calculated based on the difference between the exercise price and the fair value of our common stock. The intrinsic value of options exercised in 2023 and 2022 was $2,923 and $6,864, respectively.

The Company estimates the fair value of its option awards to employees and directors using Black-Scholes, which requires inputs and subjective assumptions, including (i) the expected stock price volatility, (ii) the calculation of the expected term of the award, (iii) the risk-free interest rate and (iv) expected dividends. Due to the lack of substantial company-specific historical and implied volatility data of its common stock, the Company has based its estimate of expected volatility on the historical volatility of a group of similar public companies. Starting in June of 2023 the Company had sufficient historical information regarding stock trading history, and started to use the Company’s own stock volatility. The Company has never paid dividends and does not expect to in the foreseeable future. The expected term of the options granted to employees is derived from the “simplified” method as described in Staff Accounting Bulletin 107 relating to stock-based compensation. The risk-free interest rates for periods within expected term of the option are based on the U.S. Treasury securities with a maturity date commensurate with the expected term of the associated award. The Company will account for actual forfeitures as they occur.

The weighted-average assumptions used to calculate the fair value of stock options granted are as follows:


	December 31, 2023		December 31, 2022
Expected dividend rate	—		—
Expected option term (years)	6.04		6.06
Expected volatility	77.87	%	73.52	%
Risk-free interest rate	3.68	%	2.04	%

Stock-based compensation expense recorded under ASC 718 related to stock options granted and common stock issued under the 2021 Employee Stock Purchase Plan were allocated to research and development and general and administrative expense as follows:


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
Research and development	$	8,572	$	5,715
General and administrative		6,050		4,954
Total stock-based compensation	$	14,622	$	10,669

c included within the condensed consolidated statements of operations is as follows:


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
Stock options	$	10,125	$	9,691
Restricted stock units		4,023		—
Restricted stock awards		228		978
Employee stock purchase plan		246		—
Total stock-based compensation	$	14,622	$	10,669

Pursuant to certain stock purchase agreements containing vesting and other provisions, the Company has the right to repurchase unvested shares.

Restricted Stock Units

The following table summarizes restricted stock activity for the year ended December 31, 2023:


		Weighted Average
	Shares	Grant Date Fair Value
Total Unvested December 31, 2022	—	$	—
Granted	3,908,729		2.86
Forfeited	(187,258)		4.05
Total Unvested December 31, 2023	3,721,471	$	2.69

As of December 31, 2023, there was $6,405 of total unrecognized compensation expense related to the unvested restricted stock with time-based vesting terms, which is expected to be recognized over a weighted average period of 2.44 years.

Restricted Stock Award

The following table summarizes restricted stock activity as of December 31, 2023:


		Weighted Average
	Shares	Grant Date Fair Value
Total Unvested December 31, 2022	193,031	$	8.41
Granted	—		—
Forfeited	(47,738)		—
Vested	(95,877)		2.50
Total Unvested December 31, 2023	49,416	$	7.27

As of December 30, 2023, there was $311 of total unrecognized compensation expense related to the unvested restricted stock with time-based vesting terms, which is expected to be recognized over a weighted average period of 1.22 years. All restricted stock vests over a four-year period.

Early-Exercise of Unvested Equity Awards

Certain equity award holders early exercised unvested equity awards. The cash received upon early exercise of options of $640 was recorded as a deposit liability on the Company’s balance sheet, totaling $640 and $1,589 as of December 31, 2023 and 2022, respectively.

Employee Stock Purchase Plan

The Employee Stock Purchase Plan was adopted by the board of directors in May 2021, a total of 564,071 shares of common stock were initially reserved for issuance under this plan, which shall be increased, upon approval of the board of directors, on January 1, 2022 and each January 1 thereafter, to the lesser of (i) on percent (1%) of the outstanding shares of common stock on the last day of the immediately preceding fiscal year, or (ii) an amount determined by the board of directors no later than the last day of the immediately preceding fiscal year. For 2022, the ESPP reserved shares were increased under the clause (i) by 550,055 shares, effective as of January 1, 2022. For 2023, the board waived the annual increase to the shares reserved under the ESPP. As of December 31, 2023, there were 1,019,241 shares available for issuance, under the ESPP.

Basic and diluted net loss per common share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Numerator
Net Income (Loss)	$ (136,673)	$ (130,932)
Denominator
Weighted-average common shares for basic net loss per share	59,314,389	57,755,842
Weighted-average common shares for diluted net loss per share	57,755,842	32,392,554
Basic net loss per common share	$ (2.30)	$ (2.27)
Diluted net loss per common share	$ (2.27)	$ (2.96)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482635/260-10-55-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (e)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 11
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 2
-Subparagraph (SX 210.5-03(25))
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-7

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
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-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-7

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-2

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-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-60B

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
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-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-4

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
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-URI https://asc.fasb.org//1943274/2147482662/260-10-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(25))
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
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Reference 15: http://www.xbrl.org/2003/role/exampleRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-7

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Financial instruments and fair value measurements

12 Months Ended

Dec. 31, 2023

Financial instruments and fair value measurements

Financial instruments and fair value measurements

Note 4—Financial instruments and fair value measurements

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2023, by level within the fair value hierarchy:


	Level 1		Level 2		Level 3		Total
Cash equivalents	$	42,263		—		—	$	42,263
U.S. Treasury		—		26,114		—		26,114
Corporate bonds		—		188,396		—		188,396
Total	$	42,263	$	214,510	$	—	$	256,773

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2022, by level within the fair value hierarchy:


	Level 1		Level 2		Level 3		Total
Cash equivalents	$	77,736		—		—	$	77,736
U.S. Treasury		—		86,475		—		86,475
Corporate bonds		—		196,603		—		196,603
Total	$	77,736	$	283,078	$	—	$	360,814

There were no transfers between levels during the years ended December 31, 2023 and 2022. The Company uses the services of its investment manager, which uses widely accepted models for assumptions in valuing securities with inputs from major third-party data providers.

The Company classifies all of its investments in fixed maturity debt securities as available-for-sale and, accordingly, are carried at estimated fair value.

The amortized cost, gross unrealized gains and losses, and fair value of investments in fixed maturity securities are as follows as of December 31, 2023:


			Gross		Gross
			Unrealized		Unrealized
	Amortized Cost		Gains		Losses		Fair Value
U.S. Treasury	$	26,070	$	44	$	—	$	26,114
Corporate bonds		188,219		399		(222)		188,396
Total	$	214,289	$	443	$	(222)	$	214,510

The amortized cost, gross unrealized gains and losses, and fair value of investments in fixed maturity securities are as follows as of December 31, 2022:


			Gross		Gross
			Unrealized		Unrealized
	Amortized Cost		Gains		Losses		Fair Value
U.S. Treasury	$	87,798	$	—	$	(1,323)	$	86,475
Corporate bonds		197,668		2		(1,067)		196,603
Total	$	285,466	$	2	$	(2,390)	$	283,078

The following table provides the maturities of the Company’s fixed maturity available-for-sale securities:


	December 31, 2023		December 31, 2022
Less than one year	$	125,414	$	231,224
One to five years		89,096		51,854
	$	214,510	$	283,078

The Company has evaluated the unrealized losses on the fixed maturity securities and determined that they are not attributable to credit risk factors. For fixed maturity securities, losses in fair value are viewed as temporary if the fixed maturity security can be held to maturity and it is reasonable to assume that the issuer will be able to service the debt, both as to principal and interest.

As of December 31, 2023 and December 31, 2022, the Company had 25 and 43 available-for-sale investment debt securities in an unrealized loss position without an allowance for credit losses, respectively. Unrealized losses on corporate debt have not been recognized into income because the issuers’ bonds are of high credit quality (rated BBB+ or higher) and the decline is fair value is largely due to market conditions and or changes in interest rates. Management does not intend to sell and it is likely that management will not be required to

sell the securities prior to the anticipated recovery of their amortized cost basis. The issuers continue to make timely payments on the bonds. The fair value is expected to recover as the bond approaches maturity.

As of December 31, 2023 and December 31, 2022, accrued interest on available-for-sale investment debt securities totaling $1,570 and $0, respectively, is excluded from the estimate of credit losses and is included in prepaid expenses and other current assets.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Impairment on Long-Lived Assets (Details) $ in Thousands	12 Months Ended
Impairment on Long-Lived Assets (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Impairment on Long-Lived Assets
Impairment	$ 16,365

Income taxes - Components of the provision for income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Current expense (benefit):
Federal	$ 418
State	1,267
Foreign	199	$ 86
Total current expense (benefit):	1,884	86
Deferred expense (benefit):
Foreign	(3)	5
Total deferred expense (benefit):	(3)	5
Total income tax expense (benefit):	$ 1,881	$ 91

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Basic and diluted net loss per common share

12 Months Ended

Dec. 31, 2023

Basic and diluted net loss per common share

Basic and diluted net loss per common share

Note 13—Basic and diluted net loss per common share

Basic and diluted net loss per common share is calculated as follows:


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
Numerator
Net loss	$	(136,673)	$	(130,932)

Denominator
Weighted-average common shares for basic and diluted net loss per share		59,314,389		57,755,842

Basic and diluted net loss per common share	$	(2.30)	$	(2.27)

The Company’s potentially dilutive securities, which include RSUs, restricted stock, warrants, early exercised stock options and stock options to purchase shares of the Company’s common stock, have been excluded from the computation of dilutive net loss per share as the effect would be antidilutive. Therefore, the weighted-average number of shares of common stock outstanding used to calculate both basic and diluted net loss per share is the same. The Company excluded the following potential shares of common stock presented based on amounts outstanding at each stated period end, from the computation of diluted net loss per share for the years ended December 31, 2023 and 2022 because including them would have had an anti-dilutive effect.


	Year Ended	Year Ended
	December 31,	December 31,
	2023	2022
Stock options to purchase common stock	8,714,660	7,489,678
Early exercised stock options subject to future vesting	119,280	470,800
Restricted stock award subject to future vesting	49,416	193,031
Unvested restricted stock units	3,721,471	—
Warrants	32,009	32,009
Total	12,636,836	8,185,518

Subsequent Events

12 Months Ended

Dec. 31, 2023

Subsequent Events

Subsequent Events

Note 18 – Subsequent Events

In the first quarter of 2024, 4,084,502 shares of common stock have been issued and sold pursuant to the Sales Agreement at a weighted-average price of $4.50 per share, resulting in approximately $18,380 in gross proceeds.

Financial instruments and fair value measurements - Transfers between levels (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Financial instruments and fair value measurements
Transfer of assets from level 1 to level 2	$ 0
Transfer of assets from level 2 to level 1	$ 0

Leases - Future minimum lease payments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Operating Leases
2024	$ 7,811
2025	8,656
2026	8,157
2027	8,342
2028	8,533
Thereafter	44,098
Total lease payments	85,597
Less: imputed Interest	(29,121)
Less: Tenant incentive receivable	(8,305)
Total	$ 48,171	$ 39,173

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies.

Commitments and Contingencies

Note 10—Commitments and contingencies

From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of its business activities. The Company accrues a liability for such matters when future expenditures are probable and such expenditures can be reasonably estimated.

Distributed Bio Master Service Agreement

On July 24, 2019, the Company entered into a Master Service Agreement with Distributed Bio, Inc (“DBio”), whereby DBio will screen for protein binders that bind to specific therapeutic targets. The Company pays for such services according to a payment schedule, and if the Company brings the protein binders into the clinic for further development, DBio will receive milestone payments of up to $16,100 in total for each product as the products move through the clinical development and regulatory approval processes. No milestone payments were due since the inception of the agreement.

The Company had $106 within accrued liabilities as of December 31, 2023 and $110 within accounts payable as of December 31, 2022, in its consolidated balance sheets related to the Master Service Agreement.

iCELL Inc. Sublicense Agreement

In March 2020, the Company entered into a Sublicense Agreement with iCELL Inc (“iCELL”) whereby iCELL granted the Company a license of certain patents and technology. The Company will pay iCELL royalties in the low single digits on net sales of the licensed product. In addition to the earned royalties, the Company will pay sales milestones, not to exceed $70,000, for the sales of the licensed product. iCELL is also eligible to receive payments of up to $4,250 in development and regulatory approval milestone payments. No milestones or royalties were due in 2023 or 2022.

Stock-based compensation - Stock-based compensation expense and by award type (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stock-based compensation
Total stock-based compensation	$ 14,622	$ 10,669
Employee Stock Option
Stock-based compensation
Total stock-based compensation	10,125	9,691
Restricted stock units
Stock-based compensation
Total stock-based compensation	4,023
Restricted stock awards
Stock-based compensation
Total stock-based compensation	228	978
Employee stock purchase plan
Stock-based compensation
Total stock-based compensation	246
Research and development
Stock-based compensation
Total stock-based compensation	8,572	5,715
General and administrative
Stock-based compensation
Total stock-based compensation	$ 6,050	$ 4,954

Commitments and Contingencies (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Mar. 31, 2020	Jun. 24, 2019
Distributed Bio Master Service Agreement
Commitments and Contingencies
Milestone payments				$ 16,100
Milestone payments due	$ 0
Distributed Bio Master Service Agreement \| Accrued expenses and other liabilities
Commitments and Contingencies
Accrued expenses	106	$ 110
iCELL Inc. Sublicense Agreement
Commitments and Contingencies
Milestone payments due	$ 0
Development and regulatory approval milestone payments			$ 4,250
iCELL Inc. Sublicense Agreement \| Maximum
Commitments and Contingencies
Milestone payments			$ 70,000

Basic and diluted net loss per common share - Schedule of potential shares of common stock excluded from computation (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Basic and diluted net loss per common share
Securities excluded from the computation of diluted net loss per share	12,636,836	8,185,518
Stock options to purchase common stock
Basic and diluted net loss per common share
Securities excluded from the computation of diluted net loss per share	8,714,660	7,489,678
Early exercised stock options subject to future vesting
Basic and diluted net loss per common share
Securities excluded from the computation of diluted net loss per share	119,280	470,800
Restricted stock award subject to future vesting
Basic and diluted net loss per common share
Securities excluded from the computation of diluted net loss per share	49,416	193,031
Unvested restricted stock units
Basic and diluted net loss per common share
Securities excluded from the computation of diluted net loss per share	3,721,471
Warrants
Basic and diluted net loss per common share
Securities excluded from the computation of diluted net loss per share	32,009	32,009

Stock-based compensation - Employee Stock Purchase Plan (Details) - shares		12 Months Ended
	Jan. 01, 2022	Dec. 31, 2022	Dec. 31, 2023
Stock based compensation
Percentage of common stock outstanding	5.00%
Employee Stock Purchase Plan 2021
Stock based compensation
Percentage of common stock outstanding		1.00%
Increase in common stock reserved		550,055
Shares available for grant			1,019,241

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of reserved shares of common stock


		Shares
Options and RSUs issued and outstanding		12,436,131
Shares available for future stock option and RSU grants		3,128,244
Shares available for employee stock purchase plan		1,019,241
Total		16,583,616

Schedule of common stock available under 2021 Incentive Plan


		Shares
Balance, December 31, 2022		5,786,358
Shares reserved for issuance		2,954,788
Options granted		(5,180,052)
RSU’s granted		(3,908,729)
Options and RSUs forfeited / cancelled		3,475,879
Balance December 31, 2023		3,128,244

Schedule of stock option activity


		Weighted Average
				Remaining		Aggregate
				Contractual		Intrinsic
				Term		Value
	Shares	Exercise Price		(years)		(in thousands)
Outstanding January 1, 2023	7,489,678	$	7.77	7.84	$	8,991
Granted	5,180,052		4.05	—		—
Exercised	(666,449)		1.01	—		—
Forfeited	(3,154,439)		7.05	—		—
Cancelled	(134,182)		12.49	—		—
Outstanding, December 31, 2023	8,714,660	$	6.24	6.89	$	3,911
Exercisable at December 31, 2023	3,938,006	$	7.11	5.66	$	2,923

Schedule of weighted-average assumptions


	December 31, 2023		December 31, 2022
Expected dividend rate	—		—
Expected option term (years)	6.04		6.06
Expected volatility	77.87	%	73.52	%
Risk-free interest rate	3.68	%	2.04	%

Schedule of Stock-based compensation expense recorded under ASC 718


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
Research and development	$	8,572	$	5,715
General and administrative		6,050		4,954
Total stock-based compensation	$	14,622	$	10,669

Schedule of stock-based compensation expense and by award type


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
Stock options	$	10,125	$	9,691
Restricted stock units		4,023		—
Restricted stock awards		228		978
Employee stock purchase plan		246		—
Total stock-based compensation	$	14,622	$	10,669

Restricted stock units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of restricted stock activity


		Weighted Average
	Shares	Grant Date Fair Value
Total Unvested December 31, 2022	—	$	—
Granted	3,908,729		2.86
Forfeited	(187,258)		4.05
Total Unvested December 31, 2023	3,721,471	$	2.69

Restricted stock

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of restricted stock activity


		Weighted Average
	Shares	Grant Date Fair Value
Total Unvested December 31, 2022	193,031	$	8.41
Granted	—		—
Forfeited	(47,738)		—
Vested	(95,877)		2.50
Total Unvested December 31, 2023	49,416	$	7.27

Bristol-Myers Squibb Collaboration (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 07, 2022 USD ($) Program item $ / shares shares	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($)
Common stock, par value \| $ / shares		$ 0.0001
Gross proceeds		$ 516	$ 345
Total transaction price		123,187
Collaboration Agreement
Number of collaboration programs \| Program	2
Additional number of collaboration programs \| Program	2
Upfront cash payment receivable	$ 100,000
Milestone payments receivable upon achievement of certain development and regulatory milestones	235,000
Amendment Fees		$ 10,000
Sales-based milestone payments	$ 500,000
Termination of Royalty term	12 years
Common stock issued \| shares	2,160,760
Common stock, par value \| $ / shares	$ 23.14
Gross proceeds	$ 50,000
Common stock, premium per share \| $ / shares	$ 7.82
Premium amount of common stock	$ 23,187
Aggregate purchase price excluding premium	$ 26,813
Number of Commitments \| item	4
FCDI Collaboration Agreement \| Collaboration Agreement
Upfront cash payment receivable	$ 10

Impairment on Long-Lived Assets

12 Months Ended

Dec. 31, 2023

Impairment on Long-Lived Assets

Impairment on Long-Lived Assets

Note 17 – Impairment of long-lived assets

During 2023, the Company made the strategic decision to consolidate multiple existing leased lab facilities in Philadelphia and Seattle. The Company completed an impairment analysis of its right of use assets related to the impacted leases along with the related property and equipment at each facility (the “Asset Groups”). The Company reviewed its long-lived assets for impairment following ASC 360 for Property, Plant, and Equipment. The Company evaluated its long-lived assets for recoverability due to changes in circumstances that indicated that the carrying amounts may not be recoverable.

The Company reviewed each Asset Group for impairment by comparing the carrying values of the assets with their estimated future undiscounted cash flows. An impairment charge was calculated as the difference between asset carrying values and fair value of discounted cash flows. Indicative fair market quotes received are considered level three fair value estimates.

The Company analyzed each Asset Group for impairment based on fair values calculated as discounted cash flows estimated to be received from the lease assets where applicable. The difference between fair value and carrying value of the Asset Groups was recognized as an impairment of $16,365 during the year ended December 31, 2023.

CONSOLIDATED BALANCE SHEETS (Parentheticals) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
CONSOLIDATED BALANCE SHEETS
Preferred Stock, Par or Stated Value Per Share	$ 0.0001
Preferred Stock, Shares Authorized	10,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0
Common Stock, Par or Stated Value Per Share	$ 0.0001
Common Stock, Shares Authorized	125,236,190	300,000,000
Common Stock, Shares, Issued	60,335,701	58,473,660
Common Stock, Shares, Outstanding	60,335,701	55,005,523

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2023	Feb. 29, 2024	Jun. 30, 2023
Document and Entity Information [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	001-40498
Entity Registrant Name	Century Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	84-2040295
Entity Address State Or Province	PA
Entity Address, Address Line One	25 N 38th Street, 11th Floor
Entity Address, City or Town	Philadelphia
Entity Address, Postal Zip Code	19104
City Area Code	267
Local Phone Number	817-5790
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	IPSC
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 131,775,555
Entity Common Stock, Shares Outstanding		64,817,863
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	Philadelphia, Pennsylvania
Entity Central Index Key	0001850119
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Summary of significant accounting policies and basis of presentation (Details)	12 Months Ended
	Dec. 31, 2023 segment
Summary of significant accounting policies and basis of presentation
Number of operating segment	1

Insider Trading Arrangements	12 Months Ended
Insider Trading Arrangements	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Accrued expenses and other liabilities

12 Months Ended

Dec. 31, 2023

Accrued expenses and other liabilities.

Accrued expenses and other liabilities

Note 7—Accrued expenses and other liabilities

The following is a summary of accrued expenses:


	December 31, 2023		December 31, 2022
Payroll and bonuses	$	6,496	$	7,062
Interest		—		117
Accrued clinical trial related costs		470		314
Professional and legal fees		1,642		1,637
Operating lease liability, current		1,513		475
Other		28		236
Total accrued expenses and other liabilities	$	10,149	$	9,841

Long-term debt - Term Loan Agreement (Details) - USD ($)	May 01, 2023	Dec. 31, 2022	Sep. 14, 2020
Long-term debt
Debt instrument end of term fee		$ (395,000)
Deferred financing costs		$ 146,000
Warrants to purchase units			16,112
Warrants term			10 years
Warrants exercise price			$ 13.96
Fair value of the warrants at issuance			$ 46,000
Loan Agreement
Long-term debt
Loan amount			10,000,000
Debt prepayment charges	$ 10,617,000
Debt instrument prepayment charge	100
Debt instrument end of term fee	$ 395
Percentage of prepayment charge on original principal amount of debt	1.00%
Tranche 1
Long-term debt
Loan amount			$ 10,000,000

Prepaid expenses and other current assets (Tables)

12 Months Ended

Dec. 31, 2023

Prepaid expenses and other current assets.

Schedule of summary of prepaid expenses and other current assets


	December 31, 2023		December 31, 2022
Research and development	$	34	$	110
Insurance		761		1,454
Software licenses and other		1,011		1,417
Income tax receivable		650		—
Reimbursement receivable		15		780
Warranties		215		242
Accrued interest receivable		1,570		—
Total prepaid expenses and other current assets	$	4,256	$	4,003

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Subsequent Events
Common stock issued and sold		60,335,701	58,473,660
Proceeds from Issuance of Common Stock		$ 516	$ 345
Sales Agreement
Subsequent Events
Common stock issued and sold	4,084,502
Weighted-average price	$ 4.50
Proceeds from Issuance of Common Stock	$ 18,380

Organization and description of the business

12 Months Ended

Dec. 31, 2023

Organization and description of the business

Organization and description of the business

CENTURY THERAPEUTICS, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

Note 1—Organization and description of the business

Century Therapeutics, Inc. (the “Company”) is an innovative biotechnology company developing transformative allogeneic cell therapies to create products for the treatment of both solid tumor and hematological malignancies, and autoimmune and inflammatory diseases with significant unmet medical need. Since inception, the Company has devoted substantially all of its time and efforts to performing research and development activities, building infrastructure and raising capital. The Company is incorporated in the state of Delaware.

Principles of Consolidation

The consolidated financial statements include the consolidated financial position and consolidated results of operations of the Company and Century Therapeutics Canada ULC. All intercompany balances and transactions have been eliminated in consolidation.

Liquidity

The accompanying consolidated financial statements have been prepared assuming the Company will continue as a going concern. The Company has limited operating history and its prospects are subject to risks, expenses, and uncertainties frequently encountered by companies in the biotechnology and pharmaceutical industries. These risks include, but are not limited to, the uncertainty of availability of additional financing and the uncertainty of achieving future profitability.

Since inception, the Company has incurred net losses and negative cash flows from operations. During the year ended December 31, 2023, the Company incurred a net loss of $136,673 and used $88,348 of cash from operations. Cash and cash equivalents and short and long-term investments were $261,834 at December 31, 2023. Management expects to incur additional losses in the future to fund its operations and conduct product research and preclinical and clinical development and recognizes the need to raise additional capital to fully implement its business plan. The Company believes it has adequate cash and financial resources to operate for at least the next 12 months from the date of issuance of these consolidated financial statements.

Reduction in Force

In January 2023, the Company’s board of directors approved, and management implemented a new portfolio prioritization and capital allocation strategy. The resulting changes included pausing investments in CNTY-103 for glioblastoma as well as a discovery program in hematologic malignancies. The Company has shifted focus to CNTY-101 and will accelerate key programs, including one follow-on candidate for lymphoma, CNTY-102, CNTY-107 for Nectin-4+ solid tumors, and CNTY-101 in moderate to sever Systemic Lupus Eythematosus (“SLE”). In addition, the Company continues its partnered programs with Bristol-Myers Squibb. The restructuring plan resulted in a reduction in the Company’s workforce of approximately 25%. In connection with the restricting plan, lab operations in Seattle and Hamilton, Ontario were closed and research activities were consolidated in Philadelphia.

Property and equipment, net

12 Months Ended

Dec. 31, 2023

Property and equipment, net

Property and equipment, net

Note 6—Property and equipment, net

The following is a summary of property and equipment, net:


	December 31, 2023		December 31, 2022
Lab equipment	$	29,597	$	28,811
Leasehold improvements		60,862		48,951
Construction in progress		124		13,998
Computer software and equipment		2,899		3,132
Furniture and fixtures		1,061		1,548
Total		94,543		96,440
Less: Accumulated depreciation		(22,838)		(13,655)
Property and equipment, net	$	71,705	$	82,785

Depreciation expense was $13,044 and $8,440 for the years ended December 31, 2023 and 2022, respectively. The Company recognized $11,422 in impairment on property and equipment, net within the consolidated December 31, 2023 financial statements. See footnote 17, Impairment of long-lived assets”.

Financial instruments and fair value measurements (Tables)

12 Months Ended

Dec. 31, 2023

Financial instruments and fair value measurements

Schedule of assets measured at fair value by level within the fair value hierarchy

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2023, by level within the fair value hierarchy:


	Level 1		Level 2		Level 3		Total
Cash equivalents	$	42,263		—		—	$	42,263
U.S. Treasury		—		26,114		—		26,114
Corporate bonds		—		188,396		—		188,396
Total	$	42,263	$	214,510	$	—	$	256,773

The following table sets forth the Company’s assets that were measured at fair value as of December 31, 2022, by level within the fair value hierarchy:


	Level 1		Level 2		Level 3		Total
Cash equivalents	$	77,736		—		—	$	77,736
U.S. Treasury		—		86,475		—		86,475
Corporate bonds		—		196,603		—		196,603
Total	$	77,736	$	283,078	$	—	$	360,814

Schedule of investments in fixed maturity securities

The amortized cost, gross unrealized gains and losses, and fair value of investments in fixed maturity securities are as follows as of December 31, 2023:


			Gross		Gross
			Unrealized		Unrealized
	Amortized Cost		Gains		Losses		Fair Value
U.S. Treasury	$	26,070	$	44	$	—	$	26,114
Corporate bonds		188,219		399		(222)		188,396
Total	$	214,289	$	443	$	(222)	$	214,510

The amortized cost, gross unrealized gains and losses, and fair value of investments in fixed maturity securities are as follows as of December 31, 2022:


			Gross		Gross
			Unrealized		Unrealized
	Amortized Cost		Gains		Losses		Fair Value
U.S. Treasury	$	87,798	$	—	$	(1,323)	$	86,475
Corporate bonds		197,668		2		(1,067)		196,603
Total	$	285,466	$	2	$	(2,390)	$	283,078

Schedule of maturities of fixed maturity available-for-sale securities


	December 31, 2023		December 31, 2022
Less than one year	$	125,414	$	231,224
One to five years		89,096		51,854
	$	214,510	$	283,078

Defined contribution plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Defined contribution plan
Defined contributions	$ 1,287	$ 862
First 3% of participating employee contributions
Defined contribution plan
Employer contribution matching percentage	100.00%
Employee contribution	3.00%
Next 2% of participating employee contributions
Defined contribution plan
Employer contribution matching percentage	50.00%
Employee contribution	2.00%

Income taxes - Income (loss) before provision for income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income taxes
Domestic	$ (135,003)	$ (131,314)
Foreign	211	473
Net Income (Loss)	(136,673)	(130,932)
Loss before provision for income taxes	$ (134,792)	$ (130,841)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Financial instruments and fair value measurements - Investments in fixed maturity securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financial instruments and fair value measurements
Amortized Cost	$ 214,289	$ 285,466
Gross Unrealized Gains	443	2
Gross Unrealized Losses	(222)	(2,390)
Fair Value	214,510	283,078
U.S. Treasury
Financial instruments and fair value measurements
Amortized Cost	26,070	87,798
Gross Unrealized Gains	44
Gross Unrealized Losses		(1,323)
Fair Value	26,114	86,475
Corporate bonds
Financial instruments and fair value measurements
Amortized Cost	188,219	197,668
Gross Unrealized Gains	399	2
Gross Unrealized Losses	(222)	(1,067)
Fair Value	$ 188,396	$ 196,603

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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+ Details

Property and equipment, net (Tables)

12 Months Ended

Dec. 31, 2023

Property and equipment, net

Schedule of summary of property and equipment, net


	December 31, 2023		December 31, 2022
Lab equipment	$	29,597	$	28,811
Leasehold improvements		60,862		48,951
Construction in progress		124		13,998
Computer software and equipment		2,899		3,132
Furniture and fixtures		1,061		1,548
Total		94,543		96,440
Less: Accumulated depreciation		(22,838)		(13,655)
Property and equipment, net	$	71,705	$	82,785

Defined contribution plan

12 Months Ended

Dec. 31, 2023

Defined contribution plan

Defined contribution plan

Note 14—Defined contribution plan

The Company has a 401(k) Employee Savings Plan (“401(k) Plan”) that is available to all employees of the Company. The Company has elected a Safe-Harbor provision for the 401(k) Plan in which participants are always fully vested in their employer contributions. The Company matches 100% of the first 3% of participating employee contributions and 50% of the next 2% of participating employee contributions. Contributions are made in cash. Contributions were approximately $1,287 and $862 for the year ended December 31, 2023 and 2022 respectively. Such contribution expense has been recognized in the consolidated statement of operations for each period.

Financial instruments and fair value measurements - Maturities of fixed maturity available-for-sale securities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2021	Dec. 31, 2022
Financial instruments and fair value measurements
Less than one year	$ 125,414,000		$ 231,224,000
One to five years	89,096,000		51,854,000
Debt securities	$ 214,510,000		$ 283,078,000
Number of available-for-sale investment debt securities	25		43
Amount of accrued interest receivable on available-for-sale investment debt securities	$ 1,570,000	$ 0

Property and equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property and equipment, net
Gross total	$ 94,543	$ 96,440
Less: Accumulated depreciation	(22,838)	(13,655)
Property and equipment, net	71,705	82,785
Depreciation	13,044	8,440
Impairment on property and equipment	$ 11,422
Impairment, Long-Lived Asset, Held-for-Use, Statement of Income or Comprehensive Income [Extensible Enumeration]	Asset Impairment Charges
Lab equipment
Property and equipment, net
Gross total	$ 29,597	28,811
Leasehold improvements
Property and equipment, net
Gross total	60,862	48,951
Construction in progress
Property and equipment, net
Gross total	124	13,998
Computer software and equipment
Property and equipment, net
Gross total	2,899	3,132
Furniture and fixtures
Property and equipment, net
Gross total	$ 1,061	$ 1,548

Accrued expenses and other liabilities (Tables)

12 Months Ended

Dec. 31, 2023

Accrued expenses and other liabilities.

Schedule of summary of accrued expenses


	December 31, 2023		December 31, 2022
Payroll and bonuses	$	6,496	$	7,062
Interest		—		117
Accrued clinical trial related costs		470		314
Professional and legal fees		1,642		1,637
Operating lease liability, current		1,513		475
Other		28		236
Total accrued expenses and other liabilities	$	10,149	$	9,841

Summary of significant accounting policies and basis of presentation - Early exercised options (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Summary of significant accounting policies and basis of presentation
Amount of deposit liability related to shares held by employees and nonemployees that were subject to repurchase	$ 640	$ 1,584
Total shares legally outstanding	60,504,397	59,137,491
Less: unvested early exercised shares	(119,280)	(470,800)
Less: unvested restricted stock awards (Note 16)	(49,416)	(193,031)
Total shares issued and outstanding	60,335,701	58,473,660

Long-term debt (Tables)

12 Months Ended

Dec. 31, 2023

Long-term debt

Summary of the Company's indebtedness


	December 31, 2023		December 31, 2022
Principal	$	—	$	10,000
Plus: End of term fee		—		395
Less: Debt discount attributable to warrants, net of accretion		—		(8)
Less: Unamortized deferred financing cost and end of term fee, net of accretion		—		(146)
Long-term debt, net	$	—	$	10,241

Schedule of interest expense attributable to the loan agreement



	For the Year Ended		For the Year Ended
	December 31, 2023		December 31, 2022
Interest expense	$	540	$	787
Amortization of debt issuance costs, including end of term fee accretion		—		230
	$	540	$	1,017

Prepaid expenses and other current assets - Summary of prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Prepaid expenses and other current assets.
Research and development	$ 34	$ 110
Insurance	761	1,454
Software licenses and other	1,011	1,417
Income tax receivable	650
Reimbursement receivable	15	780
Warranties	215	242
Other	1,570
Total prepaid expenses and other current assets	$ 4,256	$ 4,003

Summary of significant accounting policies and basis of presentation - Property and equipment and Stock-based compensation (Details)	12 Months Ended
	Dec. 31, 2023
Summary of significant accounting policies and basis of presentation
Estimated useful lives of the assets	5 years
Expected dividend rate	0.00%

Income taxes - Reconciliation of the Company statutory income tax rate to the Company effective income tax (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of the Company's statutory income tax rate to the Company's effective income tax rate
Income at US statutory rate	21.00%	21.00%
State taxes, net of federal benefit	8.70%	11.00%
Permanent differences	0.00%	0.60%
Tax credits	3.70%	1.90%
Tax law change	0.00%	0.00%
Foreign rate differential	0.00%	0.00%
Valuation allowance	(36.30%)	(33.80%)
Other	1.60%	(0.70%)
Effective tax rate	(1.30%)	0.00%

Stock-based compensation - Stock option weighted-average assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
weighted-average assumptions fair value of stock option granted
Expected dividend rate	0.00%
Employee Stock Option [Member]
weighted-average assumptions fair value of stock option granted
Expected option term (years)	6 years 14 days	6 years 21 days
Expected volatility	77.87%	73.52%
Risk-free interest rate	3.68%	2.04%