On Track to Begin and Report Initial Clinical Data from PKU Gene Therapy Trial and to Start IND-Enabling Studies in PKU Gene Editing and MLD Gene Therapy Programs Next Year

BEDFORD, Mass., Nov. 13, 2018 (GLOBE NEWSWIRE) — Homology Medicines, Inc. (Nasdaq: FIXX), a genetic medicines company, announced today financial results for the quarter ended September 30, 2018 and highlighted recent accomplishments.

“We have made substantial progress with our PKU gene therapy program, as evidenced by our long-term efficacy data that also demonstrates restoration of the biochemical pathway in PKU, and establishing GMP processes and capacity that can support the planned Phase 1/2 trial,” said Arthur Tzianabos, Ph.D., President and Chief Executive Officer of Homology Medicines. “Initial feedback from PKU physicians has reinforced the need for a treatment that can address the underlying cause of the disease, and multiple centers have expressed interest in participating in our Phase 1/2 trial in 2019. We plan to nominate a gene editing candidate for children with PKU as well as a gene therapy candidate for children with metachromatic leukodystrophy, both of which we expect to advance into IND-enabling studies next year. The build-out of our GMP manufacturing facility is nearly complete and is expected to be finished by the end of the year.”

Third Quarter 2018 and Recent Accomplishments

• Presented long-term efficacy data for HMI-102, a gene therapy candidate for phenylketonuria (PKU), demonstrating that a single in vivo dose resulted in sustained reduction of phenylalanine (Phe) to normal levels for 48 weeks post-treatment in the disease model. Additionally, levels of tyrosine increased, which is required for development of neurotransmitters, and coat color changed, which indicates melanin production. Tyrosine and melanin are byproducts of Phe metabolism, signaling a restoration of the normal biochemical pathway in the disease. These data were presented at the European Society of Gene & Cell Therapy Annual Congress.
• Presented preclinical data from metachromatic leukodystrophy (MLD) program demonstrating a single in vivo dose of gene therapy resulted in therapeutic levels of enzyme activity in the disease model. These data, as well as biodistribution data that demonstrated Homology’s AAVHSCs are able to reach the central and peripheral nervous system, were presented at the Society for Neuroscience (SfN) 2018 Annual Meeting.
• Hosted an educational webinar with the National PKU Alliance to describe the opportunity for gene therapy and gene editing to treat and potentially cure PKU. The webcast replay is available at https://youtu.be/WemExU7d9pw.
• Continued to build Phase 1/2 GMP manufacturing facility, which remains on track to be completed this year.

Third Quarter 2018 Financial Results
Collaboration revenue for the quarter ended September 30, 2018 was $1.0 million in connection with a strategic collaboration with Novartis. Collaboration revenue is being recognized on a straight-line basis over the estimated period of the performance of services.

Total operating expenses for the quarter ended September 30, 2018 were $17.2 million, compared to $6.7 million for the same period in 2017, and consisted of research and development expenses and general and administrative expenses.

Research and development expenses for the quarter ended September 30, 2018 were $13.4 million, compared to $4.9 million for the same period in 2017. The increase of $8.5 million was due to a rise in direct research expenses including contract manufacturing costs and laboratory supplies in support of pre-IND enabling studies, increased personnel costs to support the lead product development programs and research initiatives, as well as expenses related to expanding manufacturing capabilities.

General and administrative expenses for the quarter ended September 30, 2018 were $3.8 million, compared to $1.7 million for the same period in 2017. The increase of $2.1 million was primarily due to increased personnel costs as a result of new hires, increased facility costs including rent expense, and costs associated with expanded operations in support of the Company’s recent initial public offering and financial reporting requirements.

Net loss for the quarter ended September 30, 2018 was $(14.8) million or $(0.40) per share, compared to a net loss of $(6.5) million or $(2.78) per share for the same period in 2017.

As of September 30, 2018, Homology had approximately $237.5 million in cash, cash equivalents and short-term investments. Homology expects cash, cash equivalents and short-term investments to fund operations for at least the next two years.

Upcoming Events

• Evercore ISI HealthCONx Conference: November 27, 2018 at the Boston Harbor Hotel
• WORLDSymposium 2019: February 4-8, 2019 in Orlando

About Homology Medicines, Inc.
Homology Medicines, Inc. is a genetic medicines company dedicated to transforming the lives of patients suffering from rare genetic diseases with significant unmet medical needs by curing the underlying cause of the disease. Homology’s proprietary platform is designed to utilize its human hematopoietic stem cell-derived adeno-associated virus vectors (AAVHSCs) to precisely and efficiently deliver genetic medicines in vivo either through a gene therapy or nuclease-free gene editing modality across a broad range of genetic disorders. Homology has a management team with a successful track record of discovering, developing and commercializing therapeutics with a particular focus on rare diseases, and intellectual property covering its suite of 15 AAVHSCs. Homology believes that its compelling preclinical data, scientific expertise, product development strategy, manufacturing capabilities and intellectual property position it as a leader in the development of genetic medicines. For more information, please 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 statements regarding upcoming events and presentations; advancing our novel gene therapy and gene editing technology platform and pipeline; our expectations surrounding initiation of clinical trials for our PKU gene therapy program and expressions of interest in participating; the anticipated timing of completion of our GMP manufacturing facility; the anticipated timing for nominating a gene editing candidate and initiating IND-enabling studies for our PKU gene editing program; the anticipated timing for nominating a gene therapy candidate and initiating IND-enabling studies for our MLD gene therapy program; our beliefs regarding our manufacturing capabilities; our goal of improving the lives of patients with rare genetic diseases; the anticipated timing of the release of clinical data; beliefs about preclinical data; our position as a leader in the development of genetic medicines; and the sufficiency of our cash, cash equivalents and short-term investments. 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: the fact that 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 marketable products; the early stage of our development efforts; our failure or the failure of our collaborators to successfully develop and commercialize drug candidates; potential unforeseen events during clinical trials could cause delays or other adverse consequences; risks relating to the build out of our manufacturing facility; 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; the inability to obtain orphan drug exclusivity; failure to obtain international marketing approval; failure to obtain U.S. 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; the price of our common stock may be volatile; significant costs as a result of operating as a public company; and any securities class action litigation. 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, 2018 and our other filings with 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.