FIXX Homology Medicines Inc

Homology Medicines, Inc. (Nasdaq: FIXX), a genetic medicines company, announced today the successful closing of the deal with Oxford Biomedica plc (LSE: OXB) to establish an Adeno-Associated Virus (AAV) Manufacturing and Innovation Business. The new company, Oxford Biomedica Solutions LLC, incorporates Homology’s technical and manufacturing operations, team and GMP facility with OXB’s extensive know-how in viral vector manufacturing. Homology will maintain access to the capabilities that the Company built over the past four years, as well as share in potential benefits derived from future innovations as a 20% owner and preferred customer of Oxford Biomedica Solutions.

“As we move our clinical programs and pipeline forward, high-quality manufacturing from an industry-leading team remains one of our most important priorities,” said Arthur Tzianabos, Ph.D., President and Chief Executive Officer of Homology Medicines. “Our stake in Oxford Biomedica Solutions provides us with continued access to experts in our AAVHSC technology platform with the added benefits that our partnership with global viral vector manufacturing leader OXB can bring. In addition, the $130 million in non-dilutive capital will be instrumental in advancing our own programs, while we work with OXB to build what we believe will be a highly successful business offering to many companies seeking high-quality AAV products that patients deserve. We look forward to our continued work with Tim Kelly, who served as Homology’s Chief Operating Officer and built our internal manufacturing capabilities, as he assumes the CEO and Board Chair positions at Oxford Biomedica Solutions.”

In connection with Homology’s contribution of its AAV process development and manufacturing assets, including AAV experts, GMP operations and manufacturing facility to Oxford Biomedica Solutions, Homology received $130 million from OXB. Homology believes that this non-dilutive capital, together with a reduction in operating expenses relating to manufacturing, will extend the Company’s cash runway into the second half of 2024. Additionally, there is an opportunity for Homology to receive further non-dilutive funding at any time following the three-year anniversary of the agreement, which could result from the exercise of options related to OXB’s potential purchase of Homology’s ownership interest in Oxford Biomedica Solutions. MTS Health Partners served as financial advisor to Homology on the deal, and Latham and Watkins, LLP served as Homology’s legal advisor.

About Homology Medicines, Inc.Homology Medicines, Inc. is a clinical-stage genetic medicines company dedicated to transforming the lives of patients suffering from rare diseases by addressing the underlying cause of the disease. Homology’s clinical programs include HMI-102, an investigational gene therapy for adults with phenylketonuria (PKU); HMI-103, a gene editing candidate for PKU; and HMI-203, an investigational gene therapy for Hunter syndrome. Additional programs focus on metachromatic leukodystrophy (MLD), paroxysmal nocturnal hemoglobinuria (PNH) and other diseases. Homology’s proprietary platform is designed to utilize its family of 15 human hematopoietic stem cell-derived adeno-associated virus vectors (AAVHSCs) to precisely and efficiently deliver genetic medicines in vivo through a gene therapy or nuclease-free gene editing modality, as well as to deliver one-time gene therapy to produce antibodies throughout the body through the GTx-mAb platform. Homology has a management team with a successful track record of discovering, developing and commercializing therapeutics with a focus on rare diseases. Homology believes its initial clinical data and compelling preclinical data, scientific and product development expertise, and broad intellectual property position Homology as a leader in genetic medicines. For more information, visit www.homologymedicines.com.

Forward-Looking Statements This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including, without limitation, statements regarding our expectations regarding the transaction described above, including anticipated benefits, anticipated payments, future business and market opportunities, and anticipated growth resulting from the transaction; the potential, safety, efficacy, and regulatory and clinical progress of our product candidates; our position as a leader in the development of genetic medicines; and the sufficiency of our cash and cash equivalents to fund our operations; These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: we may not realize the anticipated benefits of the collaboration with Oxford Biomedica; the impact of the COVID-19 pandemic on our business and operations, including our preclinical studies and clinical trials, and on general economic conditions; we have and expect to continue to incur significant losses; our need for additional funding, which may not be available; failure to identify additional product candidates and develop or commercialize marketable products; the early stage of our development efforts; potential unforeseen events during clinical trials could cause delays or other adverse consequences; risks relating to the regulatory approval process; our product candidates may cause serious adverse side effects; inability to maintain our collaborations, or the failure of these collaborations; our reliance on third parties; failure to obtain U.S. or international marketing approval; ongoing regulatory obligations; effects of significant competition; unfavorable pricing regulations, third-party reimbursement practices or healthcare reform initiatives; product liability lawsuits; failure to attract, retain and motivate qualified personnel; the possibility of system failures or security breaches; risks relating to intellectual property and significant costs as a result of operating as a public company. These and other important factors discussed under the caption “Risk Factors” in our Quarterly Report on Form 10-Q for the quarter ended September 30, 2021 and our other filings with the Securities and Exchange Commission (“the SEC”) could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change.

Company ContactsTheresa McNeelyChief Communications Officer and Patient Advocatetmcneely@homologymedicines.com781-301-7277

Media Contact:Cara Mayfield Vice President, Patient Advocacy and Corporate Communications cmayfield@homologymedicines.com 781-691-3510