Commitments and Contingencies	12 Months Ended
Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	18. Commitments and Contingencies Operating Leases—The Company leases its facilities under non-cancelable operating leases that expire at various dates through October 2026. The Company entered into an office space lease at 121 First Street in Cambridge, Massachusetts on January 10, 2022, for 36 months, with an option to extend the lease for 3 years. As of January 1, 2022, the Company adopted ASC 842 which requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by leases. As a result of this adoption, the Company recorded a right-of-use asset and corresponding lease liability on the consolidated balance sheet. The Company continues to recognize rent expense, which is calculated as the remaining cost of the lease allocated over the remaining lease term on a straight-line basis. See Note 10 for additional information regarding the Company's operating leases. Letter of Credit—Restricted cash equivalents consist of $0.2 million of cash serving as collateral for a letter of credit issued for the Company’s office space, and $0.5 million as collateral for a corporate credit card program. As of December 31, 2022 and 2021, the Company’s restricted cash equivalents balance was $0.7 million and $0.2 million, respectively Legal Proceedings—The Company is not currently a party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or potential range of loss is probable and reasonably estimated under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company recognizes expenses for its costs related to its legal proceedings, as incurred. Royalty Payments—Between August 2016 and February 2019, the Company entered into agreements with the Grantors. Under the terms of the agreements, the Company was granted, in aggregate, $4.3 million. These grants were provided to the Company for the purpose of furthering the research and development of AMX0035 as a therapeutic benefit for ALS disease and Alzheimer’s disease. Under the terms of the arrangements, the Company would receive a tranche of funds as it completes certain milestones. Pursuant to the terms of the grant agreements, the Company has certain payment obligations that are contingent upon future events such as the achievement of commercialization or the receipt of proceeds from a revenue generating transaction resulting from the projects for which the grants are used for. Pursuant to the terms of the respective grant agreements among the Company, ALS Association and ALS Finding a Cure, the Company will be required to make royalty payments to each Grantor in the total amount equal to 150% of the grant received. The royalty payments will be achieved through a combination of the following payment methods: (i) an annual installment payment of 3% of net sales of any products developed under the project for which the grant was used for and (ii) 3% of cash proceeds resulting from revenue generating transaction under the project for which the grants are used for. During the year ended December 31, 2022, the Company recorded $1.4 million in royalty expense, which is included in cost of sales in the consolidated financial statements. Under the terms of the respective grant agreements among the Company, Alzheimer’s Drug Discovery Foundation, the Alzheimer’s Association, and Cure Alzheimer’s Fund, the Company will make royalty payments up to the maximum amount of $15.0 million to each Grantor (or $45.0 million in aggregate). The royalty payment will be made through a combination of the following payment methods: (i) 4% of annual net sales of any product commercialized from the project for which the grant was used for and directly related to the treatment of the Alzheimer’s disease and (ii) 15% of all royalties and cash proceeds resulting from revenue generating transactions associated with the projects for which the grants were used for under the grant agreements. As the conditions that would trigger royalty payments under the agreements have not occurred, no amounts have been recorded in the consolidated financial statements for the year ended December 31, 2022.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2022

Commitments and Contingencies Disclosure [Abstract]

18. Commitments and Contingencies

Operating Leases—The Company leases its facilities under non-cancelable operating leases that expire at various dates through October 2026. The Company entered into an office space lease at 121 First Street in Cambridge, Massachusetts on January 10, 2022, for 36 months, with an option to extend the lease for 3 years. As of January 1, 2022, the Company adopted ASC 842 which requires lessees to recognize assets and liabilities on the balance sheet for the rights and obligations created by leases. As a result of this adoption, the Company recorded a right-of-use asset and corresponding lease liability on the consolidated balance sheet. The Company continues to recognize rent expense, which is calculated as the remaining cost of the lease allocated over the remaining lease term on a straight-line basis. See Note 10 for additional information regarding the Company's operating leases.

Letter of Credit—Restricted cash equivalents consist of $0.2 million of cash serving as collateral for a letter of credit issued for the Company’s office space, and $0.5 million as collateral for a corporate credit card program. As of December 31, 2022 and 2021, the Company’s restricted cash equivalents balance was $0.7 million and $0.2 million, respectively

Legal Proceedings—The Company is not currently a party to any material legal proceedings. At each reporting date, the Company evaluates whether or not a potential loss amount or potential range of loss is probable and reasonably estimated under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company recognizes expenses for its costs related to its legal proceedings, as incurred.

Royalty Payments—Between August 2016 and February 2019, the Company entered into agreements with the Grantors. Under the terms of the agreements, the Company was granted, in aggregate, $4.3 million. These grants were provided to the Company for the purpose of furthering the research and development of AMX0035 as a therapeutic benefit for ALS disease and Alzheimer’s disease. Under the terms of the arrangements, the Company would receive a tranche of funds as it completes certain milestones. Pursuant to the terms of the grant agreements, the Company has certain payment obligations that are contingent upon future events such as the achievement of commercialization or the receipt of proceeds from a revenue generating transaction resulting from the projects for which the grants are used for.

Pursuant to the terms of the respective grant agreements among the Company, ALS Association and ALS Finding a Cure, the Company will be required to make royalty payments to each Grantor in the total amount equal to 150% of the grant received. The royalty payments will be achieved through a combination of the following payment methods: (i) an annual installment payment of 3% of net sales of any products developed under the project for which the grant was used for and (ii) 3% of cash proceeds resulting from revenue generating transaction under the project for which the grants are used for. During the year ended December 31, 2022, the Company recorded $1.4 million in royalty expense, which is included in cost of sales in the consolidated financial statements.

Under the terms of the respective grant agreements among the Company, Alzheimer’s Drug Discovery Foundation, the Alzheimer’s Association, and Cure Alzheimer’s Fund, the Company will make royalty payments up to the maximum amount of $15.0 million to each Grantor (or $45.0 million in aggregate). The royalty payment will be made through a combination of the following payment methods: (i) 4% of annual net sales of any product commercialized from the project for which the grant was used for and directly related to the treatment of the Alzheimer’s disease and (ii) 15% of all royalties and cash proceeds resulting from revenue generating transactions associated with the projects for which the grants were used for under the grant agreements. As the conditions that would trigger royalty payments under the agreements have not occurred, no amounts have been recorded in the consolidated financial statements for the year ended December 31, 2022.