0000950170-24-060556 | 10-Q | XBRL Viewer

Stock-Based Compensation - Assumptions used for the fair value of stock awards (Details)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility		98.10%
Risk-free interest rate		4.10%
Expected term (in years)		5 years 6 months
Restricted stock units \| Equity Incentive Plan 2014 \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	1 year
Restricted stock units \| Equity Incentive Plan 2014 \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years

- 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

Fair Value Measurements - Schedule of the activity in warrant liability (Details) $ in Thousands	3 Months Ended
Mar. 31, 2024 USD ($)
Fair Value Measurements
Fair value at beginning	$ 1,253
Change in fair value of liability	(649)
Fair value at ending	604
Series A warrants
Fair Value Measurements
Fair value at beginning	15
Change in fair value of liability	(15)
Fair value at ending	0
Series B warrants
Fair Value Measurements
Fair value at beginning	1,238
Change in fair value of liability	(634)
Fair value at ending	$ 604

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ (5,566)	$ 1,001

- 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

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total share-based compensation expense	$ 296	$ 265
Unvested Stock Option
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation	$ 1,500
Weighted average period	2 years 2 months 12 days
Restricted stock units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation	$ 500
Weighted average period	2 years 3 months 18 days
Research and development expenses
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total share-based compensation expense	$ 43	31
General and administrative expenses
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total share-based compensation expense	$ 253	$ 234

- 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

Fair Value Measurements

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

Note 4. Fair Value Measurements

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table presents information about the Company’s financial liabilities measured at fair value on a recurring basis and indicates the level of the fair value hierarchy used to determine such values:


	March 31, 2024
(In thousands)	Total		Level 1		Level 2		Level 3
Liabilities
Warrant liability - Series A	$	—	$	—	$	—	$	—
Warrant liability - Series B		604		—		—		604
Total liabilities	$	604	$	—	$	—	$	604


	December 31, 2023
(In thousands)	Total		Level 1		Level 2		Level 3
Liabilities
Warrant liability - Series A	$	15	$	—	$	—	$	15
Warrant liability - Series B		1,238		—		—		1,238
Total liabilities	$	1,253	$	—	$	—	$	1,253

The Company’s Level 3 liabilities consist of the September 2022 Warrants (defined below), which were determined to be liability-classified instruments. There were no transfers between Level 1, Level 2, and Level 3 during the three months ended March 31, 2024 and 2023.

Changes in Level 3 Liabilities Measured at Fair Value on a Recurring Basis

The following table summarizes the activity in the warrant liability measured at fair value on a recurring basis using unobservable inputs (Level 3) during the three months ended March 31, 2024:


	Warrant Liability
(In thousands)	Series A			Series B			Total
Balance, December 31, 2023	$	15		$	1,238		$	1,253
Change in the fair value of liability		(15	)		(634	)		(649	)
Balance, March 31, 2024	$	—		$	604		$	604

Assumptions Used in Determining Fair Value of Liability-Classified Warrants

The fair value of the warrant liability is based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The fair value of both the Series A Warrants and the Series B Warrants (each defined below) was determined using the Black-Scholes Option Pricing Model, which uses various assumptions, including (i) fair value of the Company’s ADSs, (ii) exercise price of the warrant, (iii) expected term of the warrant, (iv) expected volatility and (v) expected risk-free interest rate.

Below are the assumptions used for the fair value calculations of the Series A Warrants and Series B Warrants (each defined below), as of March 31, 2024 and December 31, 2023:


	March 31, 2024						December 31, 2023
	Series A			Series B			Series A			Series B
Stock (ADS) price	$	1.87		$	1.87		$	3.12		$	3.12
Exercise price	$	17.00		$	17.00		$	17.00		$	17.00
Expected term (in years)		0.4			5.4			0.7			5.7
Expected volatility		85.0	%		95.0	%		85.0	%		95.0	%
Risk-free interest rate		5.4	%		4.2	%		5.1	%		3.9	%
Expected dividend yield		—			—			—			—

- 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

Shareholders' (Deficit) Equity

3 Months Ended

Mar. 31, 2024

Stockholders' Equity Note [Abstract]

Shareholders' (Deficit) Equity

Note 6. Shareholders’ (Deficit) Equity

Ordinary Shares

On June 30, 2023, the Company’s shareholders approved an increase to the number of authorized ordinary shares, par value $0.0001 (the “Ordinary Shares”), the Company can issue by 35,000,000,000 ordinary shares in addition to the number of shares outstanding on June 30, 2023. Accordingly, as of March 31, 2024 and December 31, 2023, the Company was authorized to issue up to 45,122,321,523 ordinary shares.

Currently, each ADS represents 2,000 Ordinary Shares (the “ADS Ratio”). All ADS and per ADS amounts in the accompanying condensed consolidated financial statements reflect the ADS Ratio.

March 2024 Private Placement

In March 2024, the Company entered into a definitive purchase agreement with certain existing investors, pursuant to which the Company sold and issued in a private placement an aggregate of 1,320,614 ADSs at $1.48 per ADS, for aggregate gross proceeds of approximately $2.0 million (the “March 2024 Private Placement”). Net proceeds from the March 2024 Private Placement were approximately $1.7 million after deducting placement agent fees and other expenses.

At close of the March 2024 Private Placement, the Company issued to Paulson Investment Company, LLC (“Paulson”), as placement agent for the March 2024 Private Placement, warrants to purchase 132,061 ADSs at an exercise price of $1.85 per ADS (representing 125% of the purchase price per ADS sold in the March 2024 Private Placement) and a term expiring on March 27, 2029 (the “March 2024 Placement Agent Warrants”). The estimated fair value of the March 2024 Placement Agent Warrants on the issuance date was approximately $0.2 million.

The Company determined that the March 2024 Placement Agent Warrants met all of the criteria for equity classification. Accordingly, upon closing of the March 2024 Private Placement, each of the March 2024 Placement Agent Warrants were recorded as a component of additional paid-in capital.

December 2023 Private Placement

In December 2023, the Company entered into purchase agreements to sell, in a private placement, to existing investors, Dr. Ray Prudo, M.D., the Company’s Chairman, and Dr. Samir Patel, M.D., director, (the “December 2023 Private Placement”) an aggregate of 947,868 ADSs at $2.11 per ADS, for aggregate gross proceeds of approximately $2.0 million. Net proceeds from the December 2023 Private Placement were approximately $1.8 million after deducting placement agent fees and other expenses.

September 2023 Private Placement

In September 2023, the Company entered into purchase agreements to sell in a private placement to existing investors and directors, including Dr. Prudo and Ms. Rachelle Jacques, the Company’s then President and Chief Executive Officer (the “September 2023 Private Placement”) an aggregate of 551,816 ADSs at $3.30 per ADS, and pre-funded warrants (the “Pre-Funded Warrants”) to purchase up to 48,387 ADSs at a purchase price per Pre-Funded Warrant of $3.10, for aggregate gross proceeds of approximately $2.0 million. The Pre-Funded Warrants are exercisable at an exercise price of $0.20 per ADS and will not expire until exercised in full. The September 2023 Private Placement closed in October 2023 resulting in net proceeds of approximately $1.7 million after deducting placement agent fees and other expenses.

At close of the September 2023 Private Placement, the Company issued to Paulson, as placement agent for the September 2023 Private Placement, warrants to purchase 42,550 ADSs at an exercise price of $4.13 per ADS (representing 125% of the purchase price per ADS sold in the September 2023 Private Placement) and a term expiring on October 6, 2028 (the “October 2023 Placement Agent Warrants”). The estimated fair value of the October 2023 Placement Agent Warrants on the issuance date was approximately $0.1 million.

The Company determined that the Pre-Funded Warrants and October 2023 Placement Agent Warrants met all of the criteria for equity classification. Accordingly, upon closing of the September 2023 Private Placement, each of the Pre-Funded Warrants and October 2023 Placement Agent Warrants were recorded as a component of additional paid-in capital.

March 2023 Registered Direct Offering

On March 31, 2023, the Company entered into securities purchase agreements with certain accredited and institutional investors, including Dr. Prudo (the “March Registered Direct Offering”) providing for the issuance of an aggregate of 1,333,333 ADSs in a registered direct offering at $3.00 per ADS, resulting in gross proceeds of approximately $4.0 million. Net proceeds from the March Registered Direct Offering were approximately $3.5 million after deducting placement agent fees and expenses.

Warrants

In connection with various financing transactions, the Company has issued warrants to purchase the Company’s ordinary shares represented by ADSs. The Company accounts for such warrants as equity instruments or liabilities, depending on the specific terms of the warrant agreement. See Note 2 for further details on accounting policies related to the Company’s warrants.

The following table summarizes the Company’s outstanding warrants as of March 31, 2024 and December 31, 2023:


	Number of Warrant ADSs
	March 31,		December 31,		Weighted-Average
	2024		2023		Exercise Price		Expiration Date
Equity-classified Warrants
2019 Investor Warrants		59,211		59,211	$	60.00	7/1/2024
2019 Placement Warrants		8,881		8,881	$	57.00	6/28/2024
2020 Investor Warrants		139,882		139,882	$	44.00	Feb-Mar 2025
2020 Placement Warrants		22,481		22,481	$	51.00	Feb-Mar 2025
July 2021 Placement Agent Warrants		19,919		19,919	$	46.40	7/7/2026
December 2021 Investor Warrants		107,775		107,775	$	33.00	1/4/2027
December 2021 Placement Agent Warrants		8,622		8,622	$	35.00	12/29/2026
March 2022 Investor Warrants		186,020		186,020	$	28.00	3/10/2027
March 2022 Placement Agent Warrants		14,882		14,882	$	30.00	3/10/2027
October 2023 Investor Prefunded Warrants		48,387		48,387	$	0.20		—
October 2023 Placement Agent Warrants		42,550		42,550	$	4.13	10/6/2028
March 2024 Placement Agent Warrants		132,061		—	$	1.85	3/27/2029
		790,671		658,610
Liability-classified Warrants
September 2022 Series A Investor Warrants		755,000		755,000	$	17.00	9/14/2024
September 2022 Series B Investor Warrants		755,000		755,000	$	17.00	9/14/2029
		1,510,000		1,510,000
Total outstanding		2,300,671		2,168,610

The following table summarizes the Company’s warrants activity for the three months ended March 31, 2024:


	Number of		Weighted-Average
($ in thousands, except per share data)	Warrants		Exercise Price
Outstanding at December 31, 2023		2,168,610	$	21.97
Issued		132,061		1.85
Exercised		—		—
Expired		—		—
Outstanding at March 31, 2024		2,300,671	$	20.82

Capital Redemption Reserve

In December 2020, for the purposes of changing the nominal value of the Company's ordinary shares from £0.01 to $0.0001 the Company issued 3,847,331,913 deferred shares (the "Deferred Shares") of $0.01315. The Deferred Shares were created for technical reasons of company law and did not increase the aggregate value of share capital. Also in December 2020, the Deferred Shares were purchased by the Company in accordance with their terms of issue for aggregate consideration of $0.01 and immediately cancelled. The aggregate nominal value at cancellation was $50.6 million.

Amounts transferred from share capital on the redemption of the Deferred Shares of $50.6 million, along with the resulting foreign currency effect of the redenomination of Company ordinary shares of $1.6 million, are classified as "capital redemption reserve" within the Company's condensed consolidated balance sheets and condensed statements of shareholders' (deficit) equity.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481004/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

+ Details

Description of Business

3 Months Ended

Mar. 31, 2024

Description of Business

Description of Business

Note 1. Description of Business

Business Overview

Akari Therapeutics, Plc, (the “Company” or “Akari”) is incorporated in the United Kingdom. The Company is a clinical-stage biotechnology company focused on developing advanced therapies for autoimmune and inflammatory diseases involving the complement component 5 (“C5”) and leukotriene B4 (“LTB4”) pathways. The Company’s activities since inception have consisted of performing research and development activities and raising capital.

The Company is subject to a number of risks similar to those of clinical stage companies, including dependence on key individuals, uncertainty of product development and generation of revenues, dependence on outside sources of capital, risks associated with clinical trials of products, dependence on third-party collaborators for research and development operations, need for marketing authorization of products, risks associated with protection of intellectual property, and competition with larger, better-capitalized companies.

To fully execute its business plan, the Company will need, among other things, to complete its research and development efforts and clinical and regulatory activities. These activities may take several years and will require significant operating and capital expenditures in the foreseeable future. There can be no assurance that these activities will be successful. If the Company is not successful in these activities it could delay, limit, reduce or terminate preclinical studies, clinical trials or other research and development activities.

Agreement and Plan of Merger

As further described in Note 3, in March 2024, the Company entered into an Agreement and Plan of Merger with Peak Bio, Inc. (“Peak Bio”). However, the Company has prepared these condensed consolidated financial statements as if the Company will remain an independent company.

Liquidity and Financial Condition

The Company follows the provisions of Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 205-40, Presentation of Financial Statements—Going Concern, which requires management to assess the Company’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued.

The Company has incurred substantial losses and negative cash flows since inception and had an accumulated deficit of $233.0 million as of March 31, 2024. The Company’s cash balance of $1.3 million as of March 31, 2024 is not sufficient to fund its operations for the one-year period after the date these condensed consolidated financial statements are issued. These factors raise substantial doubt about the Company’s ability to continue as a going concern. The accompanying condensed consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The condensed consolidated financial statements do not include any adjustments related to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.

The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales of its product candidates currently in development. The Company is subject to a number of risks and uncertainties similar to those of other companies of the same size within the biotechnology industry, such as uncertainty of clinical trial outcomes, uncertainty of additional funding, and history of operating losses. Substantial additional financing will be needed by the Company to fund its operations and to commercially develop its product candidates. Management is currently evaluating different strategies to obtain the required funding for future operations. These

strategies may include, but are not limited to: product development financing, private placements and/or public offerings of equity and/or debt securities, and strategic research and development collaborations and/or similar arrangements. There can be no assurance that these future funding efforts will be successful.

Nasdaq Continued Listing Rules

On April 5, 2024, the Company received a letter (“Letter”) from the Listing Qualifications Staff (the “Staff”) of The Nasdaq Capital Market (“Nasdaq”) notifying the Company that the Company’s shareholders’ equity as reported in its Form 10-K is no longer in compliance with the minimum shareholders’ equity requirement for continued listing on Nasdaq under Nasdaq Listing Rule 5550(b)(1), which requires listed companies to maintain shareholders’ equity of at least $2.5 million (the “Shareholders’ Equity Requirement”). As reported on the Form 10-K, the Company’s shareholders’ deficit as of December 31, 2023 was approximately $0.2 million. The Letter has no immediate impact on the listing of the Company’s American Depositary Shares (“ADSs”) on Nasdaq. As of March 31, 2024, the Company had a shareholders' deficit of $3.6 million and therefore is still not in compliance with the Shareholders' Equity Requirement.

In accordance with the Nasdaq Listing Rules, the Company has 45 calendar days, or until May 20, 2024, to submit a plan to regain compliance with the Stockholders’ Equity Requirement (the “Compliance Plan”), which the Company plans to timely submit for the Staff’s consideration. If the Compliance Plan is accepted, the Staff may grant the Company an extension period of up to 180 calendar days from the date of the Letter, through October 2, 2024, to regain compliance with the Shareholders’ Equity Requirement.

There can be no assurance that the Staff will accept the Compliance Plan or, if accepted, that the Company will be able to evidence compliance with the Shareholders’ Equity Requirement during any extension period that the Staff may grant. If the Staff does not accept the Compliance Plan or if the Company is unable to regain compliance within any extension period granted by the Staff, the Staff would be required to issue a delisting determination. The Company would, at that time, be entitled to request a hearing before a Nasdaq Hearings Panel to present its Compliance Plan to regain compliance and to request a further extension period to regain compliance with the Shareholders’ Equity Requirement. The request for a hearing would stay any delisting action by the Staff.

If the Company continues to not be in compliance or it fails to meet any of the other Nasdaq continuing listing requirements, its ADSs may be subject to delisting and the Company may become subject to delisting proceedings. The Company is currently assessing its available options to regain compliance with the Shareholders' Equity Requirement.

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of share option activity and related information for employees and directors

The following is a summary of the Company’s stock option activity under the 2014 Plan and the 2023 Plan for the three months ended March 31, 2024:


($ in thousands, except share and per share data)	Stock Options			Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Outstanding at December 31, 2023		651,237,400		$	0.01		8.5	$	—
Granted		—			—
Exercised		—			—
Forfeited		—			—
Expired		(24,500,000	)		0.02
Outstanding at March 31, 2024 (1)		626,737,400		$	0.01		8.4	$	—
Exercisable at March 31, 2024		236,434,688		$	0.01		7.9	$	—

___________

(1)

Includes both vested stock options as well as unvested stock options for which the requisite service period has not been rendered but that are expected to vest based on achievement of a service condition.

Schedule of assumptions used to determine the fair value of stock granted

The weighted-average assumptions that the Company used to determine the fair value of share options granted were as follows, presented on a weighted average basis:


	2024		2023
Expected volatility		—		98.1	%
Risk-free interest rate		—		4.1	%
Expected dividend yield		—		—
Expected term (in years)		—		5.5

Summary of activity of the Company's unvested RSUs

The following table summarizes the Company’s restricted stock activity for the three months ended March 31, 2024:


	Time-based Awards
($ in thousands, except per share data)	Number of Shares			Weighted-Average Grant Date Fair Value
Nonvested shares at December 31, 2023		385,954,925		$	0.00
Granted		—			—
Forfeited		—			—
Vested		(97,578,000	)		0.00
Nonvested shares at March 31, 2024		288,376,925		$	0.00

Schedule of stock-based compensation expense in the following expense categories of its consolidated statements of operations and comprehensive loss

Total share-based compensation expense attributable to share-based payments made to employees, consultants and directors included in operating expenses in the Company's condensed consolidated statements of operations and comprehensive (loss) income for the three months ended March 31, 2024 and 2023, was as follows:


	Three Months Ended
	March 31,
($ in thousands)	2024		2023
Research and development	$	43	$	31
General and administrative		253		234
Total share-based compensation expense	$	296	$	265

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Schedule of financial liabilities measured at fair value on a recurring basis


	March 31, 2024
(In thousands)	Total		Level 1		Level 2		Level 3
Liabilities
Warrant liability - Series A	$	—	$	—	$	—	$	—
Warrant liability - Series B		604		—		—		604
Total liabilities	$	604	$	—	$	—	$	604


	December 31, 2023
(In thousands)	Total		Level 1		Level 2		Level 3
Liabilities
Warrant liability - Series A	$	15	$	—	$	—	$	15
Warrant liability - Series B		1,238		—		—		1,238
Total liabilities	$	1,253	$	—	$	—	$	1,253

Schedule of activity in the warrant liability measured at fair value on a recurring basis using unobservable inputs (Level 3)

The following table summarizes the activity in the warrant liability measured at fair value on a recurring basis using unobservable inputs (Level 3) during the three months ended March 31, 2024:


	Warrant Liability
(In thousands)	Series A			Series B			Total
Balance, December 31, 2023	$	15		$	1,238		$	1,253
Change in the fair value of liability		(15	)		(634	)		(649	)
Balance, March 31, 2024	$	—		$	604		$	604

Schedule of assumptions used for the fair value calculations of the warrants

Below are the assumptions used for the fair value calculations of the Series A Warrants and Series B Warrants (each defined below), as of March 31, 2024 and December 31, 2023:


	March 31, 2024						December 31, 2023
	Series A			Series B			Series A			Series B
Stock (ADS) price	$	1.87		$	1.87		$	3.12		$	3.12
Exercise price	$	17.00		$	17.00		$	17.00		$	17.00
Expected term (in years)		0.4			5.4			0.7			5.7
Expected volatility		85.0	%		95.0	%		85.0	%		95.0	%
Risk-free interest rate		5.4	%		4.2	%		5.1	%		3.9	%
Expected dividend yield		—			—			—			—

Shareholders' (Deficit) Equity - Additional Information (Details) $ / shares in Units, $ in Thousands		1 Months Ended			3 Months Ended
	Mar. 31, 2023 USD ($) $ / shares shares	Mar. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Sep. 30, 2023 USD ($) $ / shares shares	Mar. 31, 2024 USD ($) $ / shares shares	Mar. 31, 2023 USD ($) $ / shares	Mar. 04, 2024 $ / shares	Jun. 30, 2023 $ / shares shares	Dec. 31, 2020 £ / shares	Dec. 31, 2020 USD ($) $ / shares shares
Class of Stock [Line Items]
Number of shares authorized \| shares		45,122,321,523	45,122,321,523		45,122,321,523			35,000,000,000
Net proceeds from sale of shares					$ 1,726	$ 3,212
Nominal value of ADS (in per warrant ADS) \| (per share)	$ 0.0001	$ 0.0001	$ 0.0001		$ 0.0001	$ 0.0001		$ 0.0001	£ 0.01	$ 0.0001
Capital redemption reserve		$ 52,194	$ 52,194		$ 52,194					$ 50,600
Deferred shares issued \| shares										3,847,331,913
Deferred shares issued price per share \| $ / shares										$ 0.01315
Aggregate nominal value cancelled per share \| $ / shares										$ 0.01
Aggregate nominal value cancelled										$ 50,600
Ordinary Shares
Class of Stock [Line Items]
Nominal value of ADS (in per warrant ADS) \| $ / shares							$ 0.0001
Capital redemption reserve										$ 1,600
ADS \| Ordinary Shares
Class of Stock [Line Items]
Number of ordinary shares representing one ADS \| shares								2,000
Private Placement \| Placement agent
Class of Stock [Line Items]
Estimated fair value of the placement agent warrants				$ 100	$ 200
Private Placement \| ADS
Class of Stock [Line Items]
Aggregate ADSs issued (in shares) \| shares		1,320,614	947,868	551,816
Price per share \| $ / shares		$ 1.48	$ 2.11	$ 3.3
Percentage of the price per ADS for exercise price		125.00%		125.00%
Warrant expiration date				Oct. 06, 2028
Net proceeds from sale of shares		$ 1,700	$ 1,800
Gross proceeds from private placement		$ 2,000	$ 2,000
Warrants issued to purchase ADS (in shares) \| shares		132,061		42,550	132,061
Exercise price of warrants \| $ / shares		$ 1.85		$ 4.13	$ 1.85
Private Placement \| ADS \| Pre-Funded Warrants
Class of Stock [Line Items]
Purchase price of share \| $ / shares				$ 3.1
Aggregate gross proceeds				$ 2,000
Net proceeds from sale of shares				$ 1,700
Warrants issued to purchase ADS (in shares) \| shares				48,387
Exercise price of warrants \| $ / shares				$ 0.2
Registered direct offering \| ADS
Class of Stock [Line Items]
Aggregate ADSs issued (in shares) \| shares	1,333,333
Price per share \| $ / shares	$ 3
Proceeds from issuance of shares	$ 4,000
Net proceeds from sale of shares	$ 3,500

Subsequent Events - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended
	May 10, 2024	May 01, 2024	Mar. 31, 2024
Subsequent Event
Subsequent Event [Line Items]
Expected percentage of reduction of workforce		67.00%
Expected non cash expense relating to vesting of equity awards		$ 1.6
Subsequent Event \| Minimum
Subsequent Event [Line Items]
Expected severance and termination benefits		3.1
Subsequent Event \| Maximum
Subsequent Event [Line Items]
Expected severance and termination benefits		$ 3.2
May 2024 Convertible Notes
Subsequent Event [Line Items]
Payment terms			The May 2024 Notes bear interest at 15% per annum, which may be increased to 17% upon the occurrence of certain events of default as described therein, and the principal and all accrued but unpaid interest is due on the date that is the earlier of (a) ten (10) business days following the Company’s receipt of a U.K. research and development tax credit from HM Revenue and Customs, and (b) November 10, 2024.
Conversion description			Provided, however, at any time or times from the date of the note and until the tenth business day prior to closing of the Merger, the note holders are entitled to convert any portion of the outstanding and unpaid amount, including principal and accrued interest, into Company ADSs at a fixed conversion price equal to $1.59, subject to certain restrictions.
May 2024 Convertible Notes \| Subsequent Event
Subsequent Event [Line Items]
Gross proceeds from convertible promissory notes	$ 1.0
Interest rate per annum	15.00%
Default, interest rate percentage	17.00%
Conversion price	$ 1.59

Condensed Consolidated Statements of Operations and Comprehensive (Loss) Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating expenses:
Research and development	$ 2,279	$ 1,731
General and administrative	3,710	2,863
Loss from operations	(5,989)	(4,594)
Other income (expense):
Interest income	2	30
Change in fair value of warrant liability	649	5,587
Foreign currency exchange loss, net	(226)	(11)
Other expense, net	(2)	(11)
Total other income (expense), net	423	5,595
Net (loss) income	$ (5,566)	$ 1,001
Net (loss) income per share - basic	$ 0	$ 0
Net (loss) income per share - diluted	$ 0	$ 0
Weighted-average number of ordinary shares used in computing net (loss) income per share- basic	13,453,147,979	7,474,546,753
Weighted-average number of ordinary shares used in computing net (loss) income per share - diluted	13,453,147,979	7,573,542,457
Comprehensive (loss) income:
Net (loss) income	$ (5,566)	$ 1,001
Other comprehensive income, net of tax:
Foreign currency translation adjustment	279	2
Total other comprehensive income, net of tax	279	2
Total comprehensive (loss) income	$ (5,287)	$ 1,003

Shareholders' (Deficit) Equity (Tables)

3 Months Ended

Mar. 31, 2024

Stockholders' Equity Note [Abstract]

Schedule of summarizes the outstanding warrants

The following table summarizes the Company’s outstanding warrants as of March 31, 2024 and December 31, 2023:


	Number of Warrant ADSs
	March 31,		December 31,		Weighted-Average
	2024		2023		Exercise Price		Expiration Date
Equity-classified Warrants
2019 Investor Warrants		59,211		59,211	$	60.00	7/1/2024
2019 Placement Warrants		8,881		8,881	$	57.00	6/28/2024
2020 Investor Warrants		139,882		139,882	$	44.00	Feb-Mar 2025
2020 Placement Warrants		22,481		22,481	$	51.00	Feb-Mar 2025
July 2021 Placement Agent Warrants		19,919		19,919	$	46.40	7/7/2026
December 2021 Investor Warrants		107,775		107,775	$	33.00	1/4/2027
December 2021 Placement Agent Warrants		8,622		8,622	$	35.00	12/29/2026
March 2022 Investor Warrants		186,020		186,020	$	28.00	3/10/2027
March 2022 Placement Agent Warrants		14,882		14,882	$	30.00	3/10/2027
October 2023 Investor Prefunded Warrants		48,387		48,387	$	0.20		—
October 2023 Placement Agent Warrants		42,550		42,550	$	4.13	10/6/2028
March 2024 Placement Agent Warrants		132,061		—	$	1.85	3/27/2029
		790,671		658,610
Liability-classified Warrants
September 2022 Series A Investor Warrants		755,000		755,000	$	17.00	9/14/2024
September 2022 Series B Investor Warrants		755,000		755,000	$	17.00	9/14/2029
		1,510,000		1,510,000
Total outstanding		2,300,671		2,168,610

The following table summarizes the Company’s warrants activity for the three months ended March 31, 2024:


	Number of		Weighted-Average
($ in thousands, except per share data)	Warrants		Exercise Price
Outstanding at December 31, 2023		2,168,610	$	21.97
Issued		132,061		1.85
Exercised		—		—
Expired		—		—
Outstanding at March 31, 2024		2,300,671	$	20.82

Stock-Based Compensation (Details) - shares	3 Months Ended
Stock-Based Compensation (Details) - shares	Mar. 31, 2024	Jun. 30, 2023
2023 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of ordinary shares underlying outstanding equity awards consisting of stock options and restricted stock units	247,798,825
Number of shares remained available for future issuance	790,319,200
2023 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to grant		980,000,000
2023 and 2014 Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value of shares	100.00%
2023 and 2014 Plans \| Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	1 year
2023 and 2014 Plans \| Minimum \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	2 years
2023 and 2014 Plans \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of awards (in years)	10 years
2023 and 2014 Plans \| Maximum \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Equity Incentive Plan 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of ordinary shares underlying outstanding equity awards consisting of stock options and restricted stock units	667,315,500
Equity Incentive Plan 2014 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to grant	1,835,637,300
Number of shares available to grant	855,637,300

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2024

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Note 2. Summary of Significant Accounting Policies

Basis of presentation – The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information and the rules and regulations of the SEC and assumes that the Company will continue to operate as a going concern. Accordingly, they do not include all the information and footnotes required by U.S. GAAP for complete financial statements. These condensed consolidated financial statements have been prepared on the same basis as the Company’s annual consolidated financial statements and, in the opinion of management, reflect all adjustments, including normal and recurring adjustments, which the Company considers necessary for the fair presentation of financial information. The results of operations and comprehensive loss for the three months ended March 31, 2024 are not necessarily indicative of expected results for the fiscal year ended December 31, 2024 or any other future period. These interim condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements as of December 31, 2023 and notes thereto included in its Form 10-K, as filed with the SEC on March 29, 2024.

Principles of consolidation – The condensed consolidated financial statements include the accounts of the Company, Celsus Therapeutics, Inc., a Delaware corporation, Volution Immuno Pharmaceuticals SA, a private Swiss company, and Akari Malta Limited, a private Maltese company, each wholly-owned subsidiaries. All intercompany transactions have been eliminated.

Foreign currency – The functional currency of the Company is U.S. dollars, as that is the currency of the primary economic environment in which the Company operates as well as the currency in which it has been financed.

The reporting currency of the Company is U.S. dollars. The financial statements of certain of the Company's foreign subsidiaries are measured using their local currency as the functional currency. The Company translates its non-U.S. operations’ assets and liabilities denominated in foreign currencies into U.S. dollars at current rates of exchange as of the balance sheet date and income and expense items at the average exchange rate for the reporting period. Translation adjustments resulting from exchange rate fluctuations are recorded as foreign currency translation adjustments, a component of accumulated other comprehensive loss. Gains or losses from foreign currency transactions are included in foreign currency exchange gains/(losses).

Use of estimates – The preparation of the Company’s condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that may affect the reported amounts of assets, liabilities, expenses and related disclosures. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the valuation of share-based awards, the valuation of warrant liabilities, research and development prepayments, accruals and related expenses, and the valuation allowance for deferred income taxes. The Company bases its estimates on historical experience, known trends and other market-specific or other relevant factors that it believes to be reasonable under the circumstances. Estimates are periodically reviewed considering changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results may differ from those estimates or assumptions.

Concentration of credit risk – Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash. The Company generally maintains balances in various operating accounts at financial institutions in amounts that may exceed federally insured limits. The Company has not experienced any losses related to its cash and does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.

Fair value measurements – Certain assets and liabilities are carried at fair value under U.S. GAAP. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. As a basis for considering such assumptions, ASC 820, Fair Value Measurements and Disclosures (“ASC 820”) establishes a three-tier value hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value:

•

Level 1 – quoted prices in active markets for identical assets and liabilities.

•

Level 2 – inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices in active markets for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

•

Level 3 – unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Determining which category an asset or liability falls within the hierarchy requires significant judgment. The Company evaluates its hierarchy disclosures each reporting period. The fair value hierarchy also requires the Company to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value.

The carrying values of the Company’s cash, prepaid expenses and other current assets, accounts payable and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities. The Company’s liability-classified warrants are recorded at their estimated fair value. See Note 4.

Cash – The Company considers all highly-liquid investments with original maturities of 90 days or less at the time of acquisition to be cash equivalents. The Company had no cash equivalents as of March 31, 2024 or December 31, 2023.

Prepaid expenses – Payments made prior to the receipt of goods or services are capitalized until the goods or services are received.

Other current assets – Other current assets as of March 31, 2024 and December 21, 2023 were principally comprised of Value Added Tax (“VAT”) receivables.

Patent acquisition costs – Patent acquisition costs and related capitalized legal fees are amortized on a straight-line basis over the shorter of the legal or economic life. The estimated useful life is 22 years. The Company expenses costs associated with maintaining and defending patents after their issuance in the period incurred. Amortization expense for each of the three months ended March 31, 2024 and 2023 was less than $0.1 million.

Accrued expenses – As part of the process of preparing the condensed consolidated financial statements, the Company estimates accrued expenses. This process involves identifying services that third parties have performed on the Company’s behalf and estimating the level of service performed and the associated cost incurred on these services as of each balance sheet date in the Company’s condensed consolidated financial statements. Examples of estimated accrued expenses include contract service fees in conjunction with pre-clinical and clinical trials, professional service fees and contingent liabilities. In connection with these service fees, the Company’s estimates are most affected by its understanding of the status and timing of services provided relative to the actual services incurred by the service providers. If the Company does not identify certain costs that have been incurred or it under or over-estimates the level of services or costs of such services, the Company’s reported expenses for a reporting period could be understated or overstated. The date on which certain services commence, the level of services performed on or before a given date, and the cost of services are often subject to the Company’s estimation and judgment. The Company makes these judgments based upon the facts and circumstances known to it in accordance with U.S. GAAP. See Note 5.

Warrant Liability – The Company accounts for ordinary share or ADS warrants as either equity instruments, liabilities or derivative liabilities in accordance with ASC Topic 480, Distinguishing Liabilities from Equity (“ASC 480”) and/or ASC Topic 815, Derivatives and Hedging (“ASC 815”), depending on the specific terms of the warrant agreement. Liability-classified warrants are recorded at their estimated fair values at issuance are remeasured each reporting period until they are exercised, terminated, reclassified or otherwise settled. Changes in the estimated fair value of liability-classified warrants are recorded in "change in fair value of warrant liability" in the Company’s condensed consolidated statements of operations and comprehensive (loss) income. Equity-classified warrants are recorded within "additional paid-in capital" in the Company's condensed consolidated statements of shareholders' (deficit) equity at the time of issuance and not subject to remeasurement.

Other Current Liabilities – In February 2024, the Company entered into a short-term financing arrangement with a third-party vendor to finance insurance premiums. The aggregate amount financed under this agreement was $1.1 million bearing interest at an annual rate of 7.49%. As of March 31, 2024, the balance of $0.9 million, which is included in “Other current liabilities” in the Company’s balance sheets, is scheduled to be paid in monthly installments through November 2024.

Research and development expenses – Costs associated with research and development are expensed as incurred unless there is an alternative future use in other research and development projects. Research and development expenses include, among other costs, salaries and personnel–related expenses, fees paid for contract research services, fees paid to clinical research organizations, costs incurred by outside laboratories, manufacturers and other accredited facilities in connection with clinical trials and preclinical studies.

Payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received. The Company records expenses related to clinical studies and manufacturing development activities based on its estimates of the services received and efforts expended pursuant to contracts with multiple contract research organizations and manufacturing vendors that conduct and manage these activities on its behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract, and may result in uneven cash flows. There may be instances in which payments made to the Company’s vendors will exceed the level of services provided and result in a prepayment of the expense. Payments under some of these contracts depend on factors such as the successful enrollment of subjects and the completion of clinical study milestones. In amortizing or accruing service fees, the Company estimates the time period over which services will be performed, enrollment of subjects, number of sites activated and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the Company’s estimate, the Company will adjust the accrued or prepaid expense balance accordingly.

The Company accounts for research and development tax credits at the time its realization becomes probable as a credit to research and development expenses in the condensed consolidated statements of operations and comprehensive (loss) income.

Share-based compensation expense – The Company measures all share-based awards granted to employees, directors and non-employees based on the estimated fair value on the date of grant and recognizes compensation expense of those awards over the requisite service period, which is generally the vesting period of the respective awards. Forfeitures are accounted for as they occur. The Company classifies share-based compensation expense in its condensed consolidated statements of operations and comprehensive (loss) income in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified.

The fair value of each restricted ordinary share award is determined on the date of grant based on the fair value of the Company’s ordinary shares on that same date. The fair value of each share option grant is determined on the date of grant using the Black-Scholes option pricing model, which requires inputs based on certain assumptions, including the expected stock price volatility, the expected term of the award, the risk-free interest rate, and expected dividends (See Note 7). The Company estimates stock price volatility based on the Company’s historical stock price performance over a period of time that matches the expected term of the stock options. The expected term of the Company’s options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. The expected dividend

yield is based on the fact that the Company has never paid cash dividends on ordinary shares and does not expect to pay any cash dividends in the foreseeable future.

Leases – The Company accounts for its leases in accordance with ASC 842, Leases. In accordance with ASC 842, the Company records a right-of-use (“ROU”) asset and corresponding lease liability on the balance sheet for all leases with terms longer than 12 months. Leases with an initial term of twelve months or less are not recorded on the condensed consolidated balance sheet and are recognized on a straight-line basis over the lease term. As of March 31, 2024 and December 31, 2023, the Company did not have any leases with a term longer than twelve months. Accordingly, no ROU assets and corresponding lease liabilities are included in the Company’s condensed consolidated balance sheets as of March 31, 2024 or December 31, 2023.

Income taxes – In accordance with ASC 270, Interim Reporting, and ASC 740, Income Taxes, the Company is required at the end of each interim period to determine the best estimate of its annual effective tax rate and then apply that rate in providing for income taxes on a current year-to-date (interim period) basis. For the three months ended March 31, 2024 and 2023, the Company recorded no tax expense or benefit due to the expected current year loss and its historical losses. The Company has not recorded its net deferred tax asset as of either March 31, 2024 or December 31, 2023 because it maintained a full valuation allowance against all deferred tax assets as of these dates as management has determined that it is not more likely than not that the Company will realize these future tax benefits. As of March 31, 2024 and December 31, 2023, the Company had no uncertain tax positions.

Net (loss) income per share – Basic net (loss) income per ordinary share is computed by dividing net (loss) income available to ordinary shareholders by the weighted average number of ordinary shares outstanding during the period, which includes ordinary shares underlying pre-funded warrants, as such warrant is exercisable, in whole or in part, for nominal cash consideration with no expiration date. Diluted net (loss) income per ordinary share is computed by dividing the diluted net (loss) income available to ordinary shareholders by the weighted average number of ordinary shares, including potential dilutive ordinary shares assuming the dilutive effect as determined using the treasury stock method.

For periods in which the Company has reported net losses, diluted net loss per ordinary share is the same as basic net loss per ordinary share, since dilutive ordinary shares are not assumed to have been issued if their effect is anti-dilutive. The Company reported a net loss for the three months ended March 31, 2024 and net income for the three months ended March 31, 2023.

The following potential dilutive securities, presented based on amounts outstanding at the end of each reporting period, have been excluded from the calculation of diluted net loss per share because including them would have had an anti-dilutive impact:


	Three Months Ended
	March 31,
	2024		2023
Stock options		626,737,400		513,673,885
Restricted stock units		288,376,925		21,475,400
Warrants		4,504,569,500		4,155,347,500
Total		5,419,683,825		4,690,496,785

New Accounting Pronouncements – From time to time, new accounting pronouncements are issued by the FASB and rules are issued by the SEC that the Company has or will adopt as of a specified date. Unless otherwise noted, management does not believe that any other recently issued accounting pronouncements issued by the FASB or guidance issued by the SEC had, or is expected to have, a material impact on the Company’s present or future consolidated financial statements.

Recently Issued (Not Yet Adopted) Accounting Pronouncements

In November 2023, the FASB issued Accounting Standards Update (“ASU”) 2023-07, Segment Reporting: Improvements to Reportable Segment Disclosures. This ASU modified the disclosure and presentation requirements

primarily through enhanced disclosures of significant segment expenses and clarified that single reportable segment entities must apply Topic 280 in its entirety. This guidance is effective for the Company for the year beginning January 1, 2024, with early adoption permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statement. The Company is currently assessing the impact of this guidance on its consolidated financial statements and related disclosures.

In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. This ASU improves the transparency of income tax disclosure by requiring consistent categories and greater disaggregation of information in the rate reconciliation, and income taxes paid disaggregated by jurisdiction. This guidance is effective for the Company for the year beginning January 1, 2025, with early adoption permitted. The amendments should be applied on a prospective basis, with retrospective application permitted. The Company is currently assessing the impact of this guidance on its consolidated financial statements and related disclosures.

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash	$ 1,310	$ 3,845
Prepaid expenses	1,230	299
Other current assets	232	197
Total current assets	2,772	4,341
Patent acquisition costs, net		14
Total assets	2,772	4,355
Current liabilities:
Accounts payable	3,208	1,671
Accrued expenses	1,530	1,566
Warrant liability	604	1,253
Other current liabilities	983	94
Total current liabilities	6,325	4,584
Commitments and contingencies (Note 9)
Shareholders' deficit:
Share capital of $0.0001 par value Authorized: 45,122,321,523 ordinary shares at March 31, 2024 and December 31, 2023, respectively; issued and outstanding: 15,973,121,298 and 13,234,315,298 at March 31, 2024 and December 31, 2023, respectively	1,598	1,324
Additional paid-in capital	176,443	174,754
Capital redemption reserve	52,194	52,194
Accumulated other comprehensive loss	(761)	(1,040)
Accumulated deficit	(233,027)	(227,461)
Total shareholders' deficit	(3,553)	(229)
Total liabilities and shareholders' deficit	$ 2,772	$ 4,355

Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2024

Accounting Policies [Abstract]

Basis of Presentation

Principles of Consolidation

Foreign Currency

Use of Estimates

Concentration of Credit Risk

Fair Value Measurements

•

Level 1 – quoted prices in active markets for identical assets and liabilities.

•

Level 3 – unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Cash

Prepaid Expenses

Prepaid expenses – Payments made prior to the receipt of goods or services are capitalized until the goods or services are received.

Other Current Assets

Other current assets – Other current assets as of March 31, 2024 and December 21, 2023 were principally comprised of Value Added Tax (“VAT”) receivables.

Patent Acquisition Costs

Accrued Expenses

Warrant Liability

Other Current Liabilities

Research and Development Expenses

Share-Based Compensation

yield is based on the fact that the Company has never paid cash dividends on ordinary shares and does not expect to pay any cash dividends in the foreseeable future.

Leases

Income Taxes

Net (loss) income per share


	Three Months Ended
	March 31,
	2024		2023
Stock options		626,737,400		513,673,885
Restricted stock units		288,376,925		21,475,400
Warrants		4,504,569,500		4,155,347,500
Total		5,419,683,825		4,690,496,785

New Accounting Pronouncements

Recently Issued (Not Yet Adopted) Accounting Pronouncements

Condensed Consolidated Statements of Changes in Shareholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Share Capital	Additional Paid-in Capital	Capital Redemption Reserve	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance at beginning of the year at Dec. 31, 2022	$ 1,791	$ 745	$ 167,076	$ 52,194	$ (771)	$ (217,453)
Balance at the beginning of the year (in shares) at Dec. 31, 2022		7,444,917,123
Issuance of share capital related to financing, net of issuance costs	3,502	$ 267	3,235
Issuance of share capital related to financing, net of issuance costs (in shares)		2,666,666,700
Share-based compensation	265		265
Foreign currency translation	2				2
Net (loss) income	1,001					1,001
Balance at the end of the year at Mar. 31, 2023	6,561	$ 1,012	170,576	52,194	(769)	(216,452)
Balance at the end of the year (in shares) at Mar. 31, 2023		10,111,583,823
Balance at beginning of the year at Dec. 31, 2023	(229)	$ 1,324	174,754	52,194	(1,040)	(227,461)
Balance at the beginning of the year (in shares) at Dec. 31, 2023		13,234,315,298
Issuance of share capital related to financing, net of issuance costs	1,664	$ 264	1,400
Issuance of share capital related to financing, net of issuance costs (in shares)		2,641,228,000
Vesting of restricted shares	3	$ 10	(7)
Vesting of restricted shares (in shares)		97,578,000
Share-based compensation	296		296
Foreign currency translation	279				279
Net (loss) income	(5,566)					(5,566)
Balance at the end of the year at Mar. 31, 2024	$ (3,553)	$ 1,598	$ 176,443	$ 52,194	$ (761)	$ (233,027)
Balance at the end of the year (in shares) at Mar. 31, 2024		15,973,121,298

- Definition

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

+ References

+ Details

- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

+ References + Details

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481372/852-10-55-10

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
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-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(19))
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
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+ Details

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2024	May 10, 2024
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Registrant Name	Akari Therapeutics, Plc
Entity Central Index Key	0001541157
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		15,847,391,523
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Entity File Number	001-36288
Entity Incorporation, State or Country Code	X0
Entity Tax Identification Number	98-1034922
Entity Address, Address Line One	22 Boston Wharf Road
Entity Address, Address Line Two	FL 7
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02210
City Area Code	929
Local Phone Number	274-7510
Document Quarterly Report	true
Document Transition Report	false
American Depositary Shares
Document Information [Line Items]
Title of 12(b) Security	American Depository Shares, each representing 2,000 Ordinary Shares, par value $0.0001 per share
Trading Symbol	AKTX
Security Exchange Name	NASDAQ
Ordinary shares
Document Information [Line Items]
Title of 12(b) Security	Ordinary Shares, $0.0001 par value per share*
Trading Symbol	AKTX
Security Exchange Name	NASDAQ

Shareholders' (Deficit) Equity - Summary of Company"s Warrants Activity (Details) - Warrant [Member]	3 Months Ended
	Mar. 31, 2024 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Warrants Outstanding Beginning Balance \| shares	2,168,610
Number of Warrants, Issued \| shares	132,061
Number of Warrants Outstanding, Ending Balance \| shares	2,300,671
Weighted Average Exercise Price Outstanding, Beginning Balance \| $ / shares	$ 21.97
Weighted-Average Exercise Price, Issued \| $ / shares	1.85
Weighted Average Exercise Price Outstanding, Ending Blance \| $ / shares	$ 20.82

- 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

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net (loss) income	$ (5,566)	$ 1,001
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Depreciation and amortization	13	1
Share-based compensation	296	265
Changes in fair value of the warrant liability	(649)	(5,587)
Foreign currency exchange (gains) losses	264	3
Change in assets and liabilities:
Prepaid expenses and other current assets	138	(239)
Accounts payable and accrued expenses	1,460	(324)
Net cash used in operating activities	(4,044)	(4,880)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of shares, net of issuance costs	1,726	3,212
Proceeds from employee vesting of restricted shares	3
Payments on short-term financing arrangement	(215)
Net cash provided by financing activities	1,514	3,212
Effect of exchange rates on cash	(5)
Net decrease in cash and cash equivalents	(2,535)	(1,668)
Cash at beginning of period	3,845	13,250
Cash at end of period	1,310	11,582
SUPPLEMENTAL DISCLOSURES OF NONCASH ACTIVITIES:
Financing costs in accrued expenses	62	150
Subscription receivable		$ 440
Non-cash seller-financed purchases	$ 1,105

Stock-Based Compensation

3 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

Note 7. Share-Based Compensation

2023 Equity Incentive Plan

On June 30, 2023, the Company’s shareholders approved the 2023 Equity Incentive Plan (the “2023 Plan”), which provides for the grant of stock options, both incentive stock options and nonqualified stock options, stock, with and without vesting restrictions, restricted stock units and stock appreciation rights, to be granted to employees, directors and consultants. The Company is permitted to grant up to 980,000,000 ordinary share incentive awards under the 2023 Plan.

All outstanding ordinary shares under the 2014 Equity Incentive Plan (the “2014 Plan”) relating to stock options and restricted stock units may be issued under the 2023 Plan if such awards are forfeited, cancelled or expire unexercised. Accordingly, the total number of ordinary shares that may ultimately be issued under rights granted under the 2023 Plan, including up to 855,637,300 ordinary shares subject to grants under the 2014 Plan, shall not exceed 1,835,637,300 ordinary shares. In addition, if an award issued under the 2023 Plan is terminated or results in any shares not being issued, the unissued or reacquired shares shall again be available for issuance under the 2023 Plan. As of March 31, 2024, the Company had 247,798,825 ordinary shares underlying outstanding equity awards under the 2023 Plan and 790,319,200 ordinary shares were available for future issuance under the 2023 Plan.

The 2023 and 2014 Plans provide that they be administered by the compensation committee of the board of directors. The exercise price for stock option awards may not be less than 100% of the fair market value of the Company’s ordinary shares on the date of grant and the term of awards may not be greater than ten years. The Company determines the fair value of its ordinary shares based on the quoted market price of its ADSs. Vesting periods are determined at the discretion of the compensation committee. Awards granted to employees typically vest over two to four years and directors over one year.

2014 Equity Incentive Plan

Under the 2014 Plan the Company was authorized to grant stock options, restricted stock units and other awards, to employees, members of the board of directors and consultants. Upon effectiveness of the 2023 Plan no further awards were available to be issued under the 2014 Plan. As of March 31, 2024, the Company had 667,315,500 ordinary shares underlying outstanding equity awards under the 2014 Plan, consisting of stock options and restricted stock units.

Stock Options

The following is a summary of the Company’s stock option activity under the 2014 Plan and the 2023 Plan for the three months ended March 31, 2024:


($ in thousands, except share and per share data)	Stock Options			Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Outstanding at December 31, 2023		651,237,400		$	0.01		8.5	$	—
Granted		—			—
Exercised		—			—
Forfeited		—			—
Expired		(24,500,000	)		0.02
Outstanding at March 31, 2024 (1)		626,737,400		$	0.01		8.4	$	—
Exercisable at March 31, 2024		236,434,688		$	0.01		7.9	$	—

___________

(1)

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company’s ordinary shares for those options that had exercise prices lower than the fair value of the Company’s ordinary shares.

The weighted-average grant-date fair value per share of options granted during each of the three months ended March 31, 2024 and 2023 was less than $0.01.

Option Valuation

The weighted-average assumptions that the Company used to determine the fair value of share options granted were as follows, presented on a weighted average basis:


	2024		2023
Expected volatility		—		98.1	%
Risk-free interest rate		—		4.1	%
Expected dividend yield		—		—
Expected term (in years)		—		5.5

Restricted Stock Units

The 2014 Plan provided, and the 2023 Plan provides, for the award of restricted stock units (“RSUs”). RSUs are granted to employees that are subject to time-based vesting conditions that lapse between one year and four years from date of grant, assuming continued employment. Compensation cost for time-based RSUs, which vest only on continued service, is recognized on a straight-line basis over the requisite service period based on the grant date fair of the RSUs, which is derived from the closing price of the Company’s ADSs on the date of grant.

The following table summarizes the Company’s restricted stock activity for the three months ended March 31, 2024:


	Time-based Awards
($ in thousands, except per share data)	Number of Shares			Weighted-Average Grant Date Fair Value
Nonvested shares at December 31, 2023		385,954,925		$	0.00
Granted		—			—
Forfeited		—			—
Vested		(97,578,000	)		0.00
Nonvested shares at March 31, 2024		288,376,925		$	0.00

The fair value of time-based RSUs that vested during the three months ended March 31, 2024 was approximately $0.2 million. No time-based RSUs vested during the three months ended March 31, 2023.

As of March 31, 2024, 125,729,775 ordinary shares underlying vested time-based RSUs, which have been included in the condensed consolidated statement of shareholders’ (deficit) equity, were pending issuance.

Share-Based Compensation Expense

The Company classifies share-based compensation expense in the statement of operations in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified. Total share-based compensation expense attributable to share-based payments made to employees, consultants and directors included in operating expenses in the Company's condensed consolidated statements of operations and comprehensive (loss) income for the three months ended March 31, 2024 and 2023, was as follows:


	Three Months Ended
	March 31,
($ in thousands)	2024		2023
Research and development	$	43	$	31
General and administrative		253		234
Total share-based compensation expense	$	296	$	265

As of March 31, 2024, total unrecognized compensation cost related to unvested stock options and time-based RSUs was $1.5 million and $0.5 million, respectively, which is expected to be recognized over a weighted average period of 2.2 and 2.3 years, respectively.

Stock-Based Compensation - Stock Option Activity (Details) - 2023 and 2014 Plans - $ / shares	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Options Outstanding at beginning of the period	651,237,400
Number of shares, Expired	(24,500,000)
Number of shares, Options Outstanding at end of the period	626,737,400		651,237,400
Number of shares, Exercisable options at end of the period	236,434,688
Weighted average exercise price, Outstanding at beginning of the period	$ 0.01
Weighted average exercise price, Expired	0.02
Weighted average exercise price, Outstanding at end of the period	0.01		$ 0.01
Options exercisable at end of the period, Weighted average exercise price	$ 0.01
Weighted average remaining contractual life, Options outstanding during the period (in years)	8 years 4 months 24 days		8 years 6 months
Weighted average remaining contractual term, Options exercisable at end of the period (in years)	7 years 10 months 24 days
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value per share of options granted	$ 0.01	$ 0.01

Agreement and Plan of Merger - Additional Information (Details)		3 Months Ended
	Mar. 04, 2024 USD ($) $ / shares	Mar. 31, 2024 USD ($) $ / shares	Mar. 31, 2023 USD ($) $ / shares	Dec. 31, 2023 USD ($) $ / shares	Jun. 30, 2023 $ / shares	Dec. 31, 2020 $ / shares	Dec. 31, 2020 £ / shares
Agreement and Plan of Merger [Line Items]
Share capital, par value \| (per share)		$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	£ 0.01
Cash		$ 1,310,000		$ 3,845,000
Net proceeds from sale of shares		$ 1,726,000	$ 3,212,000
Akari and Peak Bio
Agreement and Plan of Merger [Line Items]
Termination fee	$ 300,000
Minimum \| Akari
Agreement and Plan of Merger [Line Items]
Net proceeds from sale of shares	10,000,000
Maximum \| Peak Bio
Agreement and Plan of Merger [Line Items]
Cash	13,500,000
Maximum \| Akari and Peak Bio
Agreement and Plan of Merger [Line Items]
Payment for expenses related to merger transaction	$ 1,500,000
American Depository Shares
Agreement and Plan of Merger [Line Items]
Percentage of expected ownership in outstanding shares	50.00%
Akari Ordinary Shares
Agreement and Plan of Merger [Line Items]
Share capital, par value \| $ / shares	$ 0.0001
Peak Common Stock
Agreement and Plan of Merger [Line Items]
Share capital, par value \| $ / shares	$ 0.0001

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2024
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

Description of Business (Details) - USD ($) $ in Thousands	3 Months Ended
Description of Business (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Description of Business [Line Items]
Accumulated deficit	$ 233,027	$ 227,461
Cash balance	1,310	3,845
Stockholders equity requirement	2,500
Remaining shareholder's deficit required to get listed in Nasdaq listing	$ 3,600	$ 200

Commitments and Contingencies (Details) - USD ($)	3 Months Ended
Commitments and Contingencies (Details) - USD ($)	Mar. 31, 2024	Mar. 31, 2023
Loss Contingencies [Line Items]
Lease costs	$ 100,000	$ 100,000
Employee Benefit Plans
Loss Contingencies [Line Items]
Description of employee benefit plans	Under the plan, the Company matches 100% of employees’ contributions up to 5% of the annual eligible compensation contributed by each employee, subject to Internal Revenue Code limitations.
Maximum annual eligible compensation contributed by each employee	5.00%
Employee Benefit Plans \| Maximum
Loss Contingencies [Line Items]
Operating Expenses	$ 100,000	$ 100,000
Employee Benefit Plans \| U.K.
Loss Contingencies [Line Items]
Description of employee benefit plans	The Company also adopted a defined contribution pension scheme which allows for U.K. employees to make contributions and provides U.K. employees with a Company contribution of 10% of compensation, subject to U.K. law.
Maximum annual eligible compensation contributed by each employee	10.00%

Stock-Based Compensation - Summarize the activity of the company unvested RSUs (Details) - Restricted stock units - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Shares/ Units
Unvested at beginning of the period (in shares)	385,954,925
Vested (in shares)	(97,578,000)
Unvested at end of the period (in shares)	288,376,925
Weighted average grant date fair value per share
Weighted average grant date fair value per share, Beginning of the period (per share)	$ 0
Vested (per share)	0
Weighted average grant date fair value per share, End of the period (per share)	$ 0
Equity Incentive Plan 2014
Weighted average grant date fair value per share
Fair value of time-based RSUs that vested	$ 200,000	$ 0
Shares underlying vested	125,729,775

Fair Value Measurements - Assumptions used for the fair value calculations of warrants (Details)	Mar. 31, 2024 shares USD ($)	Dec. 31, 2023 shares USD ($)
Series A warrants \| Exercise price
Fair Value Measurements
Warrants outstanding, measurement input	17	17
Series A warrants \| Volatility
Fair Value Measurements
Warrants outstanding, measurement input	85	85
Series A warrants \| Stock price
Fair Value Measurements
Warrants outstanding, measurement input \| shares	1.87	3.12
Series A warrants \| Risk-free rate
Fair Value Measurements
Warrants outstanding, measurement input	5.4	5.1
Series A warrants \| Expected term (in years)
Fair Value Measurements
Warrants outstanding, measurement input	0.4	0.7
Series B warrants \| Exercise price
Fair Value Measurements
Warrants outstanding, measurement input	17	17
Series B warrants \| Volatility
Fair Value Measurements
Warrants outstanding, measurement input	95	95
Series B warrants \| Stock price
Fair Value Measurements
Warrants outstanding, measurement input \| shares	1.87	3.12
Series B warrants \| Risk-free rate
Fair Value Measurements
Warrants outstanding, measurement input	4.2	3.9
Series B warrants \| Expected term (in years)
Fair Value Measurements
Warrants outstanding, measurement input	5.4	5.7

Condensed Consolidated Statements of Changes in Shareholders' Equity (Deficit) (Parenthetical)	Mar. 31, 2024 $ / shares	Dec. 31, 2023 $ / shares	Jun. 30, 2023 $ / shares	Mar. 31, 2023 $ / shares	Dec. 31, 2020 $ / shares	Dec. 31, 2020 £ / shares
Statement of Stockholders' Equity [Abstract]
Share capital, par value \| (per share)	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	£ 0.01

Shareholders' (Deficit) Equity - outstanding warrants (Details) - American Depositary Shares - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Class of Warrant or Right [Line Items]
Equity-classified Warrants	790,671	658,610
Liability-classified Warrants	1,510,000	1,510,000
Warrants exercised	2,300,671	2,168,610
2019 Investor Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	59,211	59,211
Weighted-Average Exercise Price	$ 60
2019 Placement Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	8,881	8,881
Weighted-Average Exercise Price	$ 57
2020 Investor Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	139,882	139,882
Weighted-Average Exercise Price	$ 44
2020 Placement Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	22,481	22,481
Weighted-Average Exercise Price	$ 51
July 2021 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	19,919	19,919
Weighted-Average Exercise Price	$ 46.4
December 2021 Investor Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	107,775	107,775
Weighted-Average Exercise Price	$ 33
December 2021 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	8,622	8,622
Weighted-Average Exercise Price	$ 35
March 2022 Investor Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	186,020	186,020
Weighted-Average Exercise Price	$ 28
March 2022 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	14,882	14,882
Weighted-Average Exercise Price	$ 30
October 2023 Investor Prefunded Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	48,387	48,387
Weighted-Average Exercise Price	$ 0.2
October 2023 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	42,550	42,550
Weighted-Average Exercise Price	$ 4.13
March 2024 Placement Agent Warrants
Class of Warrant or Right [Line Items]
Equity-classified Warrants	132,061
Weighted-Average Exercise Price	$ 1.85
Series A warrants \| September 2022 Investor Warrants
Class of Warrant or Right [Line Items]
Liability-classified Warrants	755,000	755,000
Weighted-Average Exercise Price	$ 17
Series B warrants \| September 2022 Investor Warrants
Class of Warrant or Right [Line Items]
Liability-classified Warrants	755,000	755,000
Weighted-Average Exercise Price	$ 17

Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value Measurements
Financial liabilities measured at fair value	$ 604	$ 1,253
Recurring \| Series A warrants
Fair Value Measurements
Financial liabilities measured at fair value	0	15
Recurring \| Series B warrants
Fair Value Measurements
Financial liabilities measured at fair value	604	1,238
Level 3
Fair Value Measurements
Financial liabilities measured at fair value	604	1,253
Level 3 \| Recurring \| Series A warrants
Fair Value Measurements
Financial liabilities measured at fair value	0	15
Level 3 \| Recurring \| Series B warrants
Fair Value Measurements
Financial liabilities measured at fair value	$ 604	$ 1,238

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Feb. 29, 2024	Dec. 31, 2023
Summary of Significant Accounting Policies
Cash equivalents	$ 0			$ 0
Short-term finance	$ 900,000		$ 1,100,000
Short-term finance, interest rate			7.49%
Short-term debt, terms	monthly installments through November 2024.
Research and Development expenses	$ 2,279,000	$ 1,731,000
Patents [Member]
Summary of Significant Accounting Policies
Finite-Lived intangible assets, remaining amortization period	22 years
Amortization of intangible assets	$ 100,000	$ 100,000

Accrued Expenses - Summary of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accrued Liabilities, Current [Abstract]
Employee compensation and benefits	$ 418	$ 187
External research and development expenses	406	635
Professional and consulting fees	519	669
Other	187	75
Total accrued expenses	$ 1,530	$ 1,566

Summary of Significant Accounting Policies - Antidilutive securities excluded from computation of earnings per share (Details) (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Line Items]
Total	5,419,683,825	4,690,496,785
Stock options
Earnings Per Share [Line Items]
Total	626,737,400	513,673,885
Warrants
Earnings Per Share [Line Items]
Total	4,504,569,500	4,155,347,500
Restricted stock units
Earnings Per Share [Line Items]
Total	288,376,925	21,475,400

Condensed Consolidated Balance Sheets (Parenthetical)	Mar. 31, 2024 $ / shares shares	Dec. 31, 2023 $ / shares shares
Statement of Financial Position [Abstract]
Ordinary shares, par value \| (per share)	$ 0.0001	$ 0.0001
Ordinary shares, shares authorized	45,122,321,523	45,122,321,523
Ordinary shares, shares issued	15,973,121,298	13,234,315,298
Ordinary shares, shares outstanding	15,973,121,298	13,234,315,298