Benzinga | Oct 22, 2020 08:32AM EDT

Homology Medicines Reports New In Vivo Gene Therapy Development Program For Treatment Of Mucopolysaccharidosis Type II

Homology Medicines, Inc. (NASDAQ:FIXX), a genetic medicines company, announced today a new in vivo gene therapy development program for the treatment of mucopolysaccharidosis type II (MPS II), or Hunter syndrome. Development candidate HMI-203 is a potential one-time AAVHSC treatment designed to deliver functional copies of the IDS gene to multiple target organs, including the peripheral and central nervous systems (PNS and CNS), following a single I.V. administration. Homology has initiated pivotal IND-enabling studies and scaled the new construct up to 500L by leveraging its plug and play commercial manufacturing platform to support a potential regulatory submission for HMI-203.

"We are pleased to unveil our third gene therapy program, which leverages the ability of our AAVHSC vectors to cross the blood-brain-barrier and blood-nerve-barrier, as well as reach other peripheral organs involved in MPS II. Our in vivo approach broadens our CNS portfolio and differentiates Homology's HMI-203 from other programs in development for Hunter syndrome," stated Albert Seymour, Ph.D., Chief Scientific Officer of Homology Medicines. "There remains a high unmet medical need for a treatment that addresses both the peripheral and cognitive effects of this fatal disorder. Our data in the MPS II murine model showed high levels of active I2S protein expression, systemic reductions in GAG accumulation, and improvements in phenotype. We look forward to our continued work to advance this potential treatment forward for the MPS II community."

In preclinical studies, a single I.V. administration of HMI-203 resulted in systemic and CNS transduction and I2S expression, leading to a significant reduction in GAG levels in the brain, liver, heart, spleen, lung and kidney, compared to the vehicle-treated disease model. Prevention of phenotypic symptoms was also observed in the model. Secreted I2S collected from the in vivo preclinical model following HMI-203 administration was taken up by human cells in an additional in vitro experiment, which supports the potential of HMI-203 to result in cell cross-correction.

Homology plans to present data from the HMI-203 program at upcoming scientific conferences as it continues its IND-enabling studies.