The Huntington's Study Group (HSG) is a non-profit, peer-reviewed research consortium dedicated to conducting clinical trials to advance treatments for Huntington's disease and related neurodegenerative disorders. Founded in 1993 in Rochester, New York, HSG has grown to become the world's leading clinical research organization exclusively focused on Huntington's disease, having conducted over 40 clinical trials—more than any other organization globally. The consortium's work has been instrumental in developing three FDA-approved treatments for Huntington's disease chorea and establishing the gold standard assessment tools used worldwide in HD clinical research.
The Huntington's Study Group was established in 1993 by a group of neurologists and researchers who recognized the critical need for a coordinated, multicenter approach to Huntington's disease clinical research. Before HSG's formation, clinical trials for Huntington's disease were fragmented, with limited coordination between research centers and inconsistent outcome measures. The founding investigators aimed to create a network that could conduct rigorous, large-scale clinical trials with standardized protocols and validated outcome measures.
The organization was modeled after the Parkinson's Study Group (PSG), which was established in 1985 and had demonstrated the success of academic clinical trial consortia in advancing treatments for neurodegenerative diseases. HSG expanded upon this model, creating a dedicated infrastructure for Huntington's disease that has since become the template for similar efforts in other rare neurodegenerative disorders.
The HSG's mission is to accelerate treatments that make a difference for Huntington's disease through research, education, and collaboration. The organization is dedicated to improving quality of life and outcomes for those impacted by Huntington's disease by:
HSG operates through a dual structure that combines the non-profit research consortium with a for-profit Contract Research Organization (CRO):
HSG Clinical Research, Inc. is a wholly owned for-profit subsidiary that serves as the only CRO dedicated exclusively to Huntington's disease trials. This entity provides comprehensive clinical trial management services including protocol development, site recruitment, data management, regulatory affairs, and biostatistics. The dual structure allows HSG to maintain academic rigor while operating with the efficiency and flexibility of a commercial CRO.
The organization is governed by a Board of Directors composed of leading Huntington's disease researchers, patient advocates, and industry representatives. A Scientific Advisory Board provides oversight and guidance on research priorities.
HSG's network includes over 200 credentialed clinical trial sites across North America, Europe, Australia, and other regions. Each site must meet strict quality standards and demonstrate expertise in Huntington's disease clinical research.
The HSG focuses exclusively on Huntington's disease clinical research across multiple therapeutic domains:
HSG has been pivotal in developing medications to manage Huntington's disease symptoms:
Chorea Management: The organization led clinical trials for all three FDA-approved drugs for Huntington's disease chorea:
Motor Symptoms: Beyond chorea, HSG researches treatments for dystonia, bradykinesia, and gait disturbances
Cognitive Symptoms: Interventions for executive dysfunction, memory deficits, and processing speed impairment
Psychiatric Symptoms: Treatments for depression, anxiety, irritability, and psychosis
HSG leads trials targeting the underlying disease process:
Huntingtin-Lowering Approaches: ASO therapies that reduce mutant huntingtin protein production
Neuroprotective Agents: Compounds aimed at protecting neurons from degeneration
Gene Therapy Approaches: Novel vectors and delivery systems for targeted gene modulation
The HSG operates as the world's largest Huntington's disease clinical research network with credentialed trial sites worldwide. This network provides:
HSG supports trials across all phases:
The HSG has contributed to numerous landmark clinical trials that have shaped Huntington's disease treatment:
The HSG developed and validated the Unified Huntington's Disease Rating Scale (UHDRS®), an invaluable research tool that provides a uniform assessment of the clinical features and course of HD. First published in 1996, the UHDRS comprises four major components:
The UHDRS has become the gold standard for clinical trials and disease monitoring, with over 1,300 PubMed publications citing its use[1]. The scale's reliability and consistency were validated in the foundational HSG publication (PMID: 8684382)[2].
HSG-led trials resulted in the three FDA-approved drugs for Huntington's disease chorea:
| Drug | Brand Name | Approval Year | Mechanism |
|---|---|---|---|
| Tetrabenazine | Xenazine | 2008 | VMAT2 inhibitor |
| Deutetrabenazine | Austedo | 2017 | Deuterated VMAT2 inhibitor |
| Valbenazine | Ingrezza | 2023 | VMAT2 inhibitor |
HSG's Neuropsychology Working Group has been instrumental in implementing non-motor diagnostic criteria for Huntington's disease, published in 2023 (PMID: 38094638)[3]. This work addresses the increasingly recognized importance of cognitive and psychiatric symptoms in disease diagnosis and monitoring.
HSG continues to lead important clinical studies across the therapeutic pipeline:
The Huntington's disease therapeutic pipeline is robust, with multiple programs in various stages of development:
| Company | Drug | Modality | Stage |
|---|---|---|---|
| PTC Therapeutics | PTC518 | ASO | Phase 2 |
| uniQure | AMT-130 | Gene Therapy | Phase 1/2 |
| VICO Therapeutics | VICO-001 | ASO | Phase 1 |
| Wave Life Sciences | WVE-003 | ASO | Phase 1 |
| Roche/Genentech | Tominersen | ASO | Phase 3 (completed) |
The HSG Clinical Trials Corner provides regular updates on these programs (PMID: 38489195)[4], (PMID: 39973379)[5].
HSG investigators have authored over 1,300 publications on Huntington's disease research, spanning basic science, clinical trials, and outcomes research. Key publication themes include:
HSG collaborates closely with Huntington's disease patient advocacy organizations:
HSG is committed to training the next generation of Huntington's disease researchers:
HSG has fundamentally shaped Huntington's disease drug development through its coordinated approach:
Accelerated Timeline: By providing a unified network for clinical trials, HSG has significantly reduced the time required to advance therapeutic candidates from preclinical to clinical stages. The consortium's infrastructure enables rapid patient recruitment and data collection that would be impossible for individual centers.
Regulatory Engagement: HSG maintains active relationships with regulatory agencies including FDA and EMA, providing guidance on clinical trial design for Huntington's disease. This engagement has been crucial in establishing regulatory precedent for novel therapeutic endpoints and trial designs.
Standardization: The development and adoption of UHDRS as the standard outcome measure has enabled cross-trial comparisons and meta-analyses that would not be possible with heterogeneous assessment approaches.
The economic impact of HSG's work extends beyond direct therapeutic development:
HSG has established productive relationships with pharmaceutical and biotechnology companies:
These partnerships enable efficient translation of academic discoveries into clinical applications while maintaining scientific rigor and patient safety.
HSG has made significant efforts to include underrepresented populations in clinical research:
Beyond clinical trials, HSG contributes to broader healthcare provider education:
The HSG was founded in 1993, eight years after the Parkinson's Study Group (PSG) was established in 1985. Both organizations follow similar models of academic clinical trial consortia and share several methodological and operational approaches. The two organizations occasionally collaborate on research involving overlapping neurodegenerative mechanisms, particularly given the growing recognition of shared pathological pathways between Huntington's and Parkinson's diseases.
HSG adapted several key elements from the Parkinson's Study Group model:
HSG's strategic priorities for coming years include:
Related pages in NeuroWiki:
Unified Huntington's Disease Rating Scale: reliability and consistency. ↩︎
Huntington Study Group's Neuropsychology Working Group: Implementing Non-Motor Diagnostic Criteria. ↩︎
Huntington's Disease Clinical Trials Update: September 2024. ↩︎
Huntington's disease: new insights into molecular pathogenesis. ↩︎
Wearable Sensors for Quantitative Measurement of Motor Symptoms in Huntington Disease. ↩︎
Understanding the lived experience of Huntington disease: Impact on quality of life. ↩︎