FDA Fast Tracks PTC518 Huntington's Program

WARREN, N.J., Sept. 26, 2024 – PTC Therapeutics (NASDAQ: PTCT) has announced the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to its PTC518 program aimed at treating Huntington's disease. This designation is bestowed on promising treatments for conditions with significant unmet needs.

"The Fast Track designation for the PTC518 program underscores its potential to offer a disease-changing solution for Huntington's disease patients," said Matthew B. Klein, M.D., Chief Executive Officer of PTC Therapeutics. "We are eager to work closely with the FDA to advance this program as efficiently as possible."

PTC518 originated from PTC's innovative splicing platform, which previously led to the development of Evrysdi® (risdiplam) for spinal muscular atrophy. In June 2024, PTC shared positive interim data from the 12-month PIVOT-HD study involving Huntington's disease patients. The findings showed durable, dose-dependent reductions of the mutant Huntingtin protein in blood cells—reaching a 43% decrease at the 10-milligram dose—and similar reductions in cerebrospinal fluid (CSF) levels. Additionally, after 12 months, there were dose-dependent improvements in clinical metrics such as the total motor score and the cUHDRS scale. Importantly, PTC518 was found to be safe and well-tolerated, with no treatment-related spikes in neurofilament light chain (NfL) levels.

Fast Track is an FDA process designed to speed up the development and review of drugs that address critical unmet medical needs in serious or life-threatening conditions. Programs with this designation benefit from more frequent interactions with the FDA and can submit their marketing applications in stages. They may also qualify for priority review and accelerated approval.

PTC518 is an orally administered small molecule that reduces the production of the mutated Huntingtin protein responsible for neuronal damage and disease progression in Huntington's disease. This molecule is bioavailable, penetrates the blood-brain barrier, is selective, and can be titrated without being expelled from the brain.

Huntington's disease (HD) is a fatal genetic disorder of the central nervous system caused by a defective gene that produces an abnormal, toxic form of the Huntingtin protein. This leads to neuron damage and death. Typically manifesting in individuals in their 30s or 40s, HD can also present earlier as Juvenile HD or even as infantile HD in children under 10. Symptoms vary but generally include abnormal movements, speech and swallowing difficulties, cognitive decline, and behavioral changes. While treatments exist for specific symptoms, no cure or drugs currently delay the onset or progression of HD.

PTC Therapeutics, Inc. is a global biopharmaceutical company dedicated to discovering, developing, and commercializing innovative medicines that benefit individuals with rare disorders. PTC focuses on creating and globally distributing treatments that provide significant improvements for patients, particularly those with limited treatment options. The company’s strategy involves leveraging its scientific and clinical expertise and its global commercial infrastructure to bring new therapies to market, thereby maximizing value for stakeholders.