Homology Medicines Announces World’s First Gene Editing Clinical Trial for PKU
- IND Clearance of pheEDIT Study to Evaluate a One-Time Dose of Investigational HMI-103 Incorporating a Novel Nuclease-Free Gene Editing Approach -
- Company Provides Update on Enrollment in Ongoing pheNIX Trial of HMI-102 Gene Therapy for Adults with PKU -
“Today’s milestone is the culmination of our team’s tireless work to translate our gene editing technology from an academic discovery into a clinical program for people with PKU,” said
The HMI-103 pheEDIT trial is expected to enroll up to nine patients ages 18-55 years old who have been diagnosed with PKU due to PAH deficiency. Once positive safety and efficacy results are established in the adult population, Homology plans to enroll younger patients in clinical trials. The Phase 1 dose-escalation trial is designed to evaluate three doses of HMI-103 to determine the recommended dose(s) for a future trial. In addition to safety endpoints, the trial will measure serum phenylalanine (Phe) changes.
HMI-103 is designed as a one-time administration to maximize the expression of functional phenylalanine hydroxylase (PAH) in liver cells and thus restore the natural biochemical pathway that metabolizes Phe. The product candidate was developed to specifically integrate a functional PAH gene into the genome using the natural DNA repair process of homologous recombination. In addition to expression, the integration is designed to correct the cell by inactivating at least one of the mutated genes and enable that correction to persist through cell division.
Homology expects that the first patient in the pheEDIT clinical trial will be dosed following requisite
Homology also announced today an update from its ongoing Phase 2 pheNIX clinical trial evaluating HMI-102 gene therapy in adults with PKU. As of
“We continue to be encouraged by the data from our pheNIX trial and to hasten enrollment, we have expanded our Medical Affairs, Clinical Development and Operations teams to support not only pheNIX, but now pheEDIT and our Hunter syndrome gene therapy trial expected this year,” said
PKU is caused by mutations in the PAH gene, which is responsible for producing the enzyme that metabolizes Phe from dietary protein. As a result, Phe accumulates to toxic levels in the blood and brain and does not convert to melanin or the amino acid tyrosine (Tyr), a precursor to neurotransmitters. Homology’s approach to PKU with gene therapy and gene editing candidates is designed to treat both the adult and pediatric communities with one-time treatments that address the genetic cause of PKU. Since gene therapy does not integrate into the genome, it can be used in cells that are not rapidly dividing, such as an adult liver. Gene editing is designed to make a permanent correction in cells, including those that are rapidly dividing, such as a child’s liver.
About HMI-102 Gene Therapy and HMI-103 Gene Editing Product Candidates
HMI-102 is an investigational gene therapy in clinical development for the treatment of phenylketonuria (PKU) in adults. HMI-102 is designed to encode the PAH gene, which is mutated in people with PKU, and delivered via the liver-tropic AAVHSC15 vector. Homology has received Fast Track Designation and orphan drug designation for HMI-102 from the
HMI-103 is an investigational, nuclease-free gene editing product candidate ultimately designed to treat pediatric patients with PKU, whose livers are rapidly dividing, following initial clinical trials in adults. HMI-103 also uses AAVHSC15 and is designed to encode the PAH gene flanked by homology arms, or long stretches of DNA, to target the PAH region of the genome. Using the body’s natural DNA repair process of homologous recombination, the PAH gene integrates into the genome. HMI-103 is designed to express phenylalanine hydroxylase (PAH) and integrate into the PAH gene to restore the natural biochemical pathway that metabolizes phenylalanine (Phe).
About Phenylketonuria (PKU)
PKU is a rare inborn error of metabolism caused by a mutation in the PAH gene. PKU results in a loss of function of the enzyme phenylalanine hydroxylase (PAH), which is responsible for the metabolism of phenylalanine (Phe), an amino acid obtained exclusively from the diet. If left untreated, toxic levels of Phe can accumulate in the blood and result in progressive and severe neurological impairment. Currently, there are no treatment options for PKU that target the underlying genetic cause of the disease. According to the
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 surrounding the potential, safety, efficacy, and regulatory and clinical progress of our product candidates; the potential of our gene therapy and gene editing platforms, including our GTx-mAb platform; our expectations surrounding clinical trial enrollment; our plans and timing for the commencement of and the release of data from clinical trials; our beliefs regarding our manufacturing capabilities; and our position as a leader in the development of genetic medicines. 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 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; difficulties or delays enrolling patients in clinical trials; risks relating to the capabilities of our manufacturing facility; risks relating to the regulatory approval process; interim, topline and preliminary data may change as more patient data become available, and are subject to audit and verification procedures that could result in material changes in the final data; 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
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Source: Homology Medicines, Inc.