Subsequent Events	12 Months Ended
Dec. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	21. Subsequent Events Strategic Restructuring On February 10, 2025, the Company notified its employees of a strategic restructuring plan adopted by the Company’s board of directors to focus its resources on the advancement of bempikibart in patients with AA (the “Restructuring Plan”). In connection with the Restructuring Plan, the Company is discontinuing its Phase 2 renal basket clinical trial of ADX-097 and is evaluating strategic options for its tissue-targeted complement inhibitor platform, inclusive of ADX-097 and early-stage assets, in combination with other cost-saving measures. The Restructuring Plan includes a reduction in force, which the Company expects to substantially complete by the end of the second quarter of 2025. As part of this Restructuring Plan, the Company expects to incur severance and severance-related charges of approximately $1.1 million. The Company may also incur other charges or cash expenditures not currently contemplated or that cannot be currently estimated due to events that may occur as a result of, or be associated with, the Restructuring Plan. Option Repricing On February 23, 2025, the Company's board of directors approved a stock option repricing (the “Option Repricing”), which was effective on February 24, 2025 (the “Repricing Date”). The Option Repricing applied to outstanding options to purchase shares of common stock of the Company granted under the Company’s 2017 Plan and 2024 Plan (collectively, “the Plans”), which, as of the Repricing Date, were held by current employees and non-employee directors of the Company and had an exercise price in excess of the current trading price of the common stock (so-called “underwater options”) with grant dates prior to February 23, 2025 (the “Eligible Options”). As of the Repricing Date, the Eligible Options were repriced such that the exercise price per share for such Eligible Options was reduced to the closing price of the common stock on the Nasdaq Global Market on the Repricing Date (the “Repriced Exercise Price”). The total number of shares of common stock underlying all Eligible Options was 1,904,998. The Eligible Options will revert to the original exercise price (the “Original Price”) if (i) such Eligible Options are exercised prior to the one-year anniversary of the Repricing Date (the “Retention Date”), (ii) an Eligible Option holder's employment is terminated by the Company for Cause (as defined in the 2024 Plan) prior to the Retention Date, or (iii) an Eligible Option holder resigns for any reason prior to the Retention Date. If an Eligible Option holder is terminated by the Company other than for Cause prior to the Retention Date (a “Terminated Employee”), any Eligible Options vested as of the date of such termination shall be exercisable at the Repriced Exercise Price (the “Terminated Employee Vested Options”), even prior to the Retention Date; provided that any unvested Eligible Options as of the date of such termination shall revert to the Original Price as of the date of termination. The deadline to exercise any Terminated Employee Vested Options, and any other Eligible Options held by a Terminated Employee that may become vested, shall be extended (but not truncated) to the later of (a) the one-year anniversary of the Terminated Employee’s termination date and (b) to align with the Eligible Option holder’s severance period (whether now or later implemented); provided that no extension shall exceed the Terminated Employee Vested Option’s expiration date, if earlier. In the event of a change-in-control prior to the Retention Date, each Eligible Option shall retain the Repriced Exercise Price to the extent it has not otherwise reverted to the Original Price. For the avoidance of doubt, the Eligible Options as modified by the Option Repricing are subject to the severance or change-in-control provisions in the current or future employment agreements, programs, policies or plans the Company has entered into or implemented or will enter into or implement with its directors, executive officers and other employees. There were no changes to the number of shares, the vesting schedule, or the expiration date of the Repriced Options except as outlined above. Pursuant to the Plans, the Company's board of directors, as the administrator of the Plans, has discretionary authority, exercisable on such terms and conditions that it deems appropriate under the circumstances, to reduce the exercise price in effect for or effect repricing through cancellation and re-grants of outstanding options under the Plans. In approving the Option Repricing, the board of directors considered the impact of the Original Price of outstanding stock options on the incentives provided to employees and directors, the lack of retention value provided by the outstanding stock options to employees and directors, and the impact of such options on the capital structure of the Company. The Company expects that the Option Repricing will result in additional share-based compensation expense that will be recognized in the Company’s statements of operations in future periods; however, the amount of additional share-based compensation expense and the periods over which it will be recognized have not yet been determined. Exercise of Call Option by OXB (US) LLC As discussed in Notes 1 and 3, at the effective time of the merger with Homology, each person who as of immediately prior to the effective time of the Merger was a stockholder of record of Homology or had the right to receive Homology’s common stock received a CVR issued by Homology representing the contractual right to receive cash payments, if any, from the combined company upon the receipt of certain proceeds, net of permitted deductions for expenses incurred in connection with pre-merger Homology assets, from a disposition of Homology’s pre-merger assets, including any equity interests held directly or indirectly by the Company in OXB (US) LLC. On March 1, 2025, Oxford Biomedica (US), Inc. exercised its option to cause the Company to sell and transfer to Oxford Biomedica (US), Inc. all of the Company’s equity ownership interest in OXB (US) LLC. The sale price is based on a formula using the Company's pro rata share of OXB (US) LLC (10%), times a predetermined multiple of revenue for the immediately preceding 12-month period increased by OXB (US) LLC's cash balance and decreased by OXB (US) LLC's debt balance as of the exercise date. The Company and Oxford Biomedica (US), Inc. expect to finalize the transaction and pay the CVR holders by the end of the second quarter of 2025.

Subsequent Events

12 Months Ended

Dec. 31, 2024

21. Subsequent Events

Strategic Restructuring

On February 10, 2025, the Company notified its employees of a strategic restructuring plan adopted by the Company’s board of directors to focus its resources on the advancement of bempikibart in patients with AA (the “Restructuring Plan”). In connection with the Restructuring Plan, the Company is discontinuing its Phase 2 renal basket clinical trial of ADX-097 and is evaluating strategic options for its tissue-targeted complement inhibitor platform, inclusive of ADX-097 and early-stage assets, in combination with other cost-saving measures. The Restructuring Plan includes a reduction in force, which the Company expects to substantially complete by the end of the second quarter of 2025. As part of this Restructuring Plan, the Company expects to incur severance and severance-related charges of approximately $1.1 million. The Company may also incur other charges or cash expenditures not currently contemplated or that cannot be currently estimated due to events that may occur as a result of, or be associated with, the Restructuring Plan.

Option Repricing

On February 23, 2025, the Company's board of directors approved a stock option repricing (the “Option Repricing”), which was effective on February 24, 2025 (the “Repricing Date”). The Option Repricing applied to outstanding options to purchase shares of common stock of the Company granted under the Company’s 2017 Plan and 2024 Plan (collectively, “the Plans”), which, as of the Repricing Date, were held by current employees and non-employee directors of the Company and had an exercise price in excess of the current trading price of the common stock (so-called “underwater options”) with grant dates prior to February 23, 2025 (the “Eligible Options”). As of the Repricing Date, the Eligible Options were repriced such that the exercise price per share for such Eligible Options was reduced to the closing price of the common stock on the Nasdaq Global Market on the Repricing Date (the “Repriced Exercise Price”). The total number of shares of common stock underlying all Eligible Options was 1,904,998.

The Eligible Options will revert to the original exercise price (the “Original Price”) if (i) such Eligible Options are exercised prior to the one-year anniversary of the Repricing Date (the “Retention Date”), (ii) an Eligible Option holder's employment is terminated by the Company for Cause (as defined in the 2024 Plan) prior to the Retention Date, or (iii) an Eligible Option holder resigns for any reason prior to the Retention Date. If an Eligible Option holder is terminated by the Company other than for Cause prior to the Retention Date (a “Terminated Employee”), any Eligible Options vested as of the date of such termination shall be exercisable at the Repriced Exercise Price (the “Terminated Employee Vested Options”), even prior to the Retention Date; provided that any unvested Eligible Options as of the date of such termination shall revert to the Original Price as of the date of termination. The deadline to exercise any Terminated Employee Vested Options, and any other Eligible Options held by a Terminated Employee that may become vested, shall be extended (but not truncated) to the later of (a) the one-year anniversary of the Terminated Employee’s termination date and (b) to align with the Eligible Option holder’s severance period (whether now or later implemented); provided that no extension shall exceed the Terminated Employee Vested Option’s expiration date, if earlier. In the event of a change-in-control prior to the Retention Date, each Eligible Option shall retain the Repriced Exercise Price to the extent it has not otherwise reverted to the Original Price. For the avoidance of doubt, the Eligible Options as modified by the Option Repricing are subject to the severance or change-in-control provisions in the current or future employment agreements, programs, policies or plans the Company has entered into or implemented or will enter into or implement with its directors, executive officers and other employees. There were no changes to the number of shares, the vesting schedule, or the expiration date of the Repriced Options except as outlined above.

Pursuant to the Plans, the Company's board of directors, as the administrator of the Plans, has discretionary authority, exercisable on such terms and conditions that it deems appropriate under the circumstances, to reduce the exercise price in effect for or effect repricing through cancellation and re-grants of outstanding options under the Plans. In approving the Option Repricing, the board of directors considered the impact of the Original Price of outstanding stock options on the incentives provided to employees and directors, the lack of retention value provided by the outstanding stock options to employees and directors, and the impact of such options on the capital structure of the Company.

The Company expects that the Option Repricing will result in additional share-based compensation expense that will be recognized in the Company’s statements of operations in future periods; however, the amount of additional share-based compensation expense and the periods over which it will be recognized have not yet been determined.

Exercise of Call Option by OXB (US) LLC

As discussed in Notes 1 and 3, at the effective time of the merger with Homology, each person who as of immediately prior to the effective time of the Merger was a stockholder of record of Homology or had the right to receive Homology’s common stock received a CVR issued by Homology representing the contractual right to receive cash payments, if any, from the combined company upon the receipt of certain proceeds, net of permitted deductions for expenses incurred in connection with pre-merger Homology assets, from a disposition of Homology’s pre-merger assets, including any equity interests held directly or indirectly by the Company in OXB (US) LLC. On March 1, 2025, Oxford Biomedica (US), Inc. exercised its option to cause the Company to sell and transfer to Oxford Biomedica (US), Inc. all of the Company’s equity ownership interest in OXB (US) LLC. The sale price is based on a formula using the Company's pro rata share of OXB (US) LLC (10%), times a predetermined multiple of revenue for the immediately preceding 12-month period increased by OXB (US) LLC's cash balance and decreased by OXB (US) LLC's debt balance as of the exercise date. The Company and Oxford Biomedica (US), Inc. expect to finalize the transaction and pay the CVR holders by the end of the second quarter of 2025.