Related Party Transactions	6 Months Ended
Jun. 30, 2022
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	13. RELATED PARTY TRANSACTIONS Oxford Biomedica Solutions LLC As described in Note 5, the Company has significant influence over, but does not control, OXB Solutions through its noncontrolling representation on OXB Solution’s board of directors and the Company’s equity interest in OXB Solutions. In March 2022, concurrently with the closing of the transaction with OXB Solutions, the Company entered into certain ancillary agreements with OXB Solutions including a supply agreement, a lease assignment and assumption agreement, a sublease agreement and a transitional services agreement. Supply Agreement Pursuant to the terms of the Manufacturing and Supply Agreement with OXB Solutions entered into in March 2022 (the "Supply Agreement"), the Company has agreed to purchase from OXB Solutions at least 50% of its clinical supply requirements of AAV-based products during the initial term of the supply agreement. The Supply Agreement will provide for an initial term of three years, which may be extended for an additional one-year term. Under the Supply Agreement, the Company is committed to purchase a minimum number of batches of drug substance and drug product, as well as process development services, totaling approximately $27.5 million in 2022 and $29.7 million in 2023. There are no minimum purchase commitments in year three of the Supply Agreement. After the initial term, the Company will have the right to terminate the Supply Agreement for convenience or other reasons specified in the Supply Agreement upon prior written notice. Either party may terminate the Supply Agreement upon an uncured material breach by the other party or upon the bankruptcy or insolvency of the other party. During the three and six months ended June 30, 2022, the Company recorded purchases of drug substance from OXB Solutions related to the Supply Agreement of $1.5 million, as well as purchases of process development services of approximately $6.9 million and $8.0 million, respectively. These amounts are included within research and development expenses on the Company's condensed consolidated statements of operations and accrued expenses and other liabilities on the Company's condensed consolidated balance sheets. As of June 30, 2022, the amount due to OXB Solutions under the Supply Agreement was $7.0 million and was included in accrued expenses and other liabilities on the Company's condensed consolidated balance sheets. Lease Assignment and Sublease Agreement As described in Note 8, the Company leases space for research and development, manufacturing and general office space in Bedford, Massachusetts. The Company and OXB Solutions entered into a lease assignment and assumption agreement pursuant to which Homology assigned all of its right, title and interest in, to and under this lease to OXB Solutions and a sublease agreement whereby OXB Solutions subleased certain premises in its facility to Homology. However, as the Company remains jointly and severally liable for the payment of rent under this lease, the Company has not been released from being the primary obligor under such lease and therefore the related right-of-use asset and lease liability were not derecognized and remain on the Company’s condensed consolidated balance sheets. Therefore, the Company is recording sublease income from OXB Solutions as if it were subleasing the space to OXB Solutions. During the three and six months ended June 30, 2022, the Company recorded sublease income of $0.9 million and $1.2 million, respectively, related to the sublease agreement with OXB Solutions. These amounts were recognized as a reduction to lease expense in the Company's condensed consolidated statements of operations. Transitional Services Agreement Under the transitional services agreement with OXB Solutions (the “Services Agreement”), the Company is performing certain services for the benefit of OXB Solutions and OXB Solutions is performing certain services for the benefit of the Company. The term of the Services Agreement will not exceed eighteen months and lasts until the earlier of termination for convenience, termination for cause in the event of an uncured material breach, termination as a result of bankruptcy of either party, and expiration or termination of the only remaining outstanding service as set forth in the Services Agreement. Each company is fully reimbursing the other for these services. Expenses incurred by the Company for services provided by OXB Solutions recognized under the Services Agreement totaled $0.2 million for the three and six months ended June 30, 2022, and are presented within research and development expenses in the condensed consolidated statements of operations as the services related to facilities support within the Company's research and development labs. As of June 30, 2022, the amount due to OXB Solutions under the Services Agreement was $0.1 million and was included in accrued expenses and other liabilities on the Company's condensed consolidated balance sheets. The Company provided finance, human resources, IT and legal services to OXB Solutions under the Services Agreement and recognized $1.4 million and $2.0 million, respectively, for the three and six months ended June 30, 2022, for amounts to be reimbursed by OXB Solutions as a reduction to general and administrative expense in the Company's condensed consolidated statements of operations. As of June 30, 2022, the Company had a receivable balance of $4.5 million from OXB Solutions which was recorded as a component of prepaid expenses and other current assets in the Company's condensed consolidated balance sheets. This receivable balance included $3.2 million for amounts paid by the Company to vendors on OXB Solutions' behalf.

Related Party Transactions

6 Months Ended

Jun. 30, 2022

13. RELATED PARTY TRANSACTIONS

Oxford Biomedica Solutions LLC

As described in Note 5, the Company has significant influence over, but does not control, OXB Solutions through its noncontrolling representation on OXB Solution’s board of directors and the Company’s equity interest in OXB Solutions. In March 2022, concurrently with the closing of the transaction with OXB Solutions, the Company entered into certain ancillary agreements with OXB Solutions including a supply agreement, a lease assignment and assumption agreement, a sublease agreement and a transitional services agreement.

Supply Agreement

Pursuant to the terms of the Manufacturing and Supply Agreement with OXB Solutions entered into in March 2022 (the "Supply Agreement"), the Company has agreed to purchase from OXB Solutions at least 50% of its clinical supply requirements of AAV-based products during the initial term of the supply agreement. The Supply Agreement will provide for an initial term of three years, which may be extended for an additional one-year term. Under the Supply Agreement, the Company is committed to purchase a minimum number of batches of drug substance and drug product, as well as process development services, totaling approximately $27.5 million in 2022 and $29.7 million in 2023. There are no minimum purchase commitments in year three of the Supply

Agreement. After the initial term, the Company will have the right to terminate the Supply Agreement for convenience or other reasons specified in the Supply Agreement upon prior written notice. Either party may terminate the Supply Agreement upon an uncured material breach by the other party or upon the bankruptcy or insolvency of the other party.

During the three and six months ended June 30, 2022, the Company recorded purchases of drug substance from OXB Solutions related to the Supply Agreement of $1.5 million, as well as purchases of process development services of approximately $6.9 million and $8.0 million, respectively. These amounts are included within research and development expenses on the Company's condensed consolidated statements of operations and accrued expenses and other liabilities on the Company's condensed consolidated balance sheets. As of June 30, 2022, the amount due to OXB Solutions under the Supply Agreement was $7.0 million and was included in accrued expenses and other liabilities on the Company's condensed consolidated balance sheets.

Lease Assignment and Sublease Agreement

As described in Note 8, the Company leases space for research and development, manufacturing and general office space in Bedford, Massachusetts. The Company and OXB Solutions entered into a lease assignment and assumption agreement pursuant to which Homology assigned all of its right, title and interest in, to and under this lease to OXB Solutions and a sublease agreement whereby OXB Solutions subleased certain premises in its facility to Homology. However, as the Company remains jointly and severally liable for the payment of rent under this lease, the Company has not been released from being the primary obligor under such lease and therefore the related right-of-use asset and lease liability were not derecognized and remain on the Company’s condensed consolidated balance sheets. Therefore, the Company is recording sublease income from OXB Solutions as if it were subleasing the space to OXB Solutions.

During the three and six months ended June 30, 2022, the Company recorded sublease income of $0.9 million and $1.2 million, respectively, related to the sublease agreement with OXB Solutions. These amounts were recognized as a reduction to lease expense in the Company's condensed consolidated statements of operations.

Transitional Services Agreement

Under the transitional services agreement with OXB Solutions (the “Services Agreement”), the Company is performing certain services for the benefit of OXB Solutions and OXB Solutions is performing certain services for the benefit of the Company. The term of the Services Agreement will not exceed eighteen months and lasts until the earlier of termination for convenience, termination for cause in the event of an uncured material breach, termination as a result of bankruptcy of either party, and expiration or termination of the only remaining outstanding service as set forth in the Services Agreement. Each company is fully reimbursing the other for these services. Expenses incurred by the Company for services provided by OXB Solutions recognized under the Services Agreement totaled $0.2 million for the three and six months ended June 30, 2022, and are presented within research and development expenses in the condensed consolidated statements of operations as the services related to facilities support within the Company's research and development labs. As of June 30, 2022, the amount due to OXB Solutions under the Services Agreement was $0.1 million and was included in accrued expenses and other liabilities on the Company's condensed consolidated balance sheets.

The Company provided finance, human resources, IT and legal services to OXB Solutions under the Services Agreement and recognized $1.4 million and $2.0 million, respectively, for the three and six months ended June 30, 2022, for amounts to be reimbursed by OXB Solutions as a reduction to general and administrative expense in the Company's condensed consolidated statements of operations. As of June 30, 2022, the Company had a receivable balance of $4.5 million from OXB Solutions which was recorded as a component of prepaid expenses and other current assets in the Company's condensed consolidated balance sheets. This receivable balance included $3.2 million for amounts paid by the Company to vendors on OXB Solutions' behalf.