Skyhawk Therapeutics Reports Promising Nine-Month Data for Huntington's Disease Drug SKY-0515
核心洞察
SKY-0515 demonstrated a mean improvement of +0.64 points in the Composite Unified Huntington's Disease (搜索) Rating Scale at nine months, contrasting with expected natural history worsening of -0.73 points.
The investigational drug achieved dose-dependent reductions of 62% in mHTT protein (搜索) and 26% in PMS1 (搜索) mRNA, targeting two core pathogenic mechanisms of Huntington's disease (搜索).
Skyhawk has expanded its Phase 2/3 FALCON-HD trial worldwide and dosed more than 90 patients with the orally-administered RNA modulator.
Skyhawk Therapeutics (搜索) announced positive nine-month interim results from its Phase 1 clinical trial of SKY-0515, an investigational treatment for Huntington's disease (搜索) that demonstrated clinical improvement contrary to expected disease progression. The oral small molecule RNA modulator showed a mean improvement of +0.64 points in the Composite Unified Huntington's Disease Rating Scale (cUHDRS) from baseline, compared to the expected natural history worsening of -0.73 points over nine months in symptomatic patients.
Biomarker Activity and Safety Profile
Treatment with SKY-0515 produced dose-dependent reductions of mHTT protein (搜索) in blood of 62% at the 9mg dose, representing what researchers describe as the greatest extent of mHTT reduction demonstrated by any therapeutic tested to date in patients. The drug also achieved dose-dependent PMS1 (搜索) mRNA reduction of 26%. PMS1 serves as a key driver of somatic CAG repeat expansion and Huntington's disease (搜索) pathology, offering a complementary mechanism to mutant HTT reduction.
The investigational therapy demonstrated excellent central nervous system exposure and has been generally safe and well tolerated across all tested doses. Patients receiving SKY-0515 in the Part C patient cohort showed mean cUHDRS improvement from baseline at three, six, and nine months.
"I am very encouraged by these safety and early efficacy data from SKY-0515's Phase 1 Part C trial in patients, showing divergence in cUHDRS away from expected natural history deterioration at the three, six, and nine month prespecified analyses," said Ed Wild, Professor of Neurology at University College London. "SKY-0515 continues to reduce mHTT protein (搜索) to the greatest extent demonstrated by any therapeutic tested to date in patients, with clinical and biomarker data showing the drug is well tolerated at all doses tested."
Dual Mechanism Approach
SKY-0515's ability to target both mHTT and PMS1 (搜索) proteins offers what researchers characterize as a potent combination for treating Huntington's disease (搜索) via two of its core pathogenic mechanisms. The drug was developed through Skyhawk's proprietary RNA-modulating platform, SKYSTAR®, and represents the company's first drug in clinical trials.
"Our goal for our Phase 1 study was to establish safety and biomarker activity," said Sergey Paushkin, Head of R&D at Skyhawk Therapeutics (搜索). "The continued strength of SKY-0515's biomarker response in our nine month interim data analysis – and the improvement in the potential endpoint, cUHDRS, compared to a worsening of the cUHDRS score in the natural history data for patients - underscores SKY-0515's potential as a best in class disease-modifying therapy for HD."
Clinical Trial Program Expansion
The company announced that its SKY-0515 Phase 2/3 FALCON-HD trial has expanded worldwide beyond its initial twelve sites in Australia and New Zealand. Skyhawk has now dosed more than 90 patients with SKY-0515 across its clinical program.
The Phase 1 clinical trial evaluated safety, tolerability, pharmacokinetics, and pharmacodynamics in healthy volunteers and individuals with early-stage Huntington's disease (搜索). Part C of the study employed a double-blind placebo-controlled parallel design examining two dose levels of SKY-0515 and placebo in individuals with early-stage HD for 84 days, followed by a 12-month extension of active treatment.
FALCON-HD represents a randomized, double-blind, placebo-controlled, dose-ranging study designed to evaluate pharmacodynamics, safety, and efficacy in 120 participants with Stage 2 and early Stage 3 HD across sites in Australia and New Zealand, plus 400 participants across 40+ worldwide sites. Eligible patients receive once-daily oral doses of SKY-0515 at one of three dose levels or placebo for at least 12 months.
Addressing Unmet Medical Need
Huntington's disease (搜索) affects over 40,000 symptomatic patients in the United States, with hundreds of thousands estimated to be affected worldwide. The rare, hereditary, and ultimately fatal neurodegenerative disorder currently has no approved treatments that slow or halt disease progression.
Wild emphasized the potential transformative impact of an orally administered huntingtin-lowering treatment for patients worldwide, noting that the open-label trial results await validation in the ongoing placebo-controlled FALCON-HD trial.
Skyhawk expects to advance additional small molecule drugs for rare neurological diseases with no approved disease-modifying therapies into clinical trials by the end of 2027.