Skyhawk Therapeutics Reports 15-Month SKY-0515 Results

Waltham, Massachusetts, U.S., September 16, 2026

SKY-0515 Targets Huntington’s Disease Biology

Huntington’s disease is a progressive genetic neurological disorder caused by an expanded CAG repeat in the HTT gene. The resulting mutant huntingtin protein contributes to progressive neuronal dysfunction and degeneration, leading to movement abnormalities, cognitive decline, and psychiatric symptoms. Because the underlying genetic cause is known, researchers have been investigating approaches that directly target huntingtin RNA or protein production. SKY-0515 is being developed using Skyhawk’s RNA splicing technology platform. The investigational compound is designed to selectively alter the processing of HTT RNA, with the objective of reducing production of the mutant huntingtin protein while maintaining expression of the normal huntingtin allele. This allele-selective approach is intended to address the disease-associated genetic mechanism while potentially preserving the physiological functions of normal huntingtin. The Phase 1/2 study was designed to evaluate SKY-0515 in people living with Huntington’s disease and generate initial clinical evidence regarding the therapy’s safety and pharmacological effects. The 15-month follow-up provides additional information beyond the initial treatment period and is important for understanding how the therapy behaves over an extended period.

Fifteen-Month Data Extend Clinical Evidence

The final analysis provides longer-term follow-up on participants who received SKY-0515. According to Skyhawk, the study continued to demonstrate a generally favorable safety and tolerability profile, with treatment-related findings monitored throughout the follow-up period. Long-term safety monitoring is particularly important for therapies intended to modify disease-associated molecular pathways in chronic neurodegenerative conditions. The company also reported pharmacodynamic findings demonstrating biological activity consistent with the intended mechanism of SKY-0515. Such measurements are important because they help researchers determine whether an investigational therapy is reaching and affecting its intended molecular target in humans. The extended data are being used to characterize the durability of target engagement and biological effects associated with SKY-0515. However, early-stage clinical studies are not designed to definitively establish efficacy. Larger and appropriately controlled studies will be necessary to determine whether changes in molecular or clinical measures translate into meaningful slowing of Huntington’s disease progression.

RNA Therapeutics Advance in Neurodegeneration

The development of SKY-0515 reflects the expanding application of RNA therapeutics to neurological and genetic diseases. RNA-targeting technologies can potentially influence disease biology at an earlier stage in the molecular pathway, before abnormal proteins accumulate or trigger downstream cellular damage. Skyhawk’s approach focuses on RNA splicing, a biological process through which cells process RNA transcripts before producing proteins. By selectively modifying this process, the company aims to develop medicines capable of controlling production of disease-associated proteins without directly editing genomic DNA. The company’s broader platform is being applied to neurological and genetic diseases where abnormal RNA processing or protein expression contributes to disease. Huntington’s disease represents a particularly important setting for this approach because the underlying genetic mutation and disease-associated protein are well characterized.

The latest 15-month results provide additional clinical experience with SKY-0515 and support continued investigation of the therapy. The data may also help inform future clinical-study design, including considerations around dose selection, treatment duration, biomarker monitoring, and patient populations. As development continues, additional studies will be needed to establish whether SKY-0515 can produce clinically meaningful benefits for people with Huntington’s disease. Demonstrating sustained molecular activity is an important component of development, but regulators and clinicians will ultimately require evidence from adequately designed clinical trials showing that the treatment provides meaningful benefits while maintaining an acceptable safety profile. Skyhawk Therapeutics’ announcement therefore represents a notable milestone in the development of RNA-based therapies for Huntington’s disease. The completion of 15 months of clinical follow-up provides researchers with a longer-term view of SKY-0515 and its biological effects in patients. Continued clinical development will determine whether the investigational therapy can translate its RNA-targeting mechanism into a potential disease-modifying treatment strategy for this progressive neurodegenerative disorder.

Source: Skyhawk Therapeutics press release