Valbenazine statistically improves chorea, a movement disorder commonly associated with Huntington’s disease, when compared with placebo, according to a recent international study led by UTHealth Houston researcher Erin Furr Stimming, MD, who served as principal investigator on behalf of the KINECT-HD Huntington Study Group.
The results of the study—which were published online today and will appear in the June 2023 print issue of Lancet Neuroscience — come one year after Fore Stemming, professor of neurology and Memorial Hermann Chair at UTHealth Houston’s McGovern School of Medicine, presented an early summary of the findings at the 2022 American Academy of Neurology Annual Meeting in Seattle.
The positive study results remind us that there is cause for hope. Chorea associated with Huntington’s disease can negatively affect quality of life and functional independence; Therefore, studying additional medications to treat these distinct motor symptoms is imperative.”
Vore Stemming, MD, director of the American Huntington’s Disease Society Center of Excellence at UTHealth Houston Neurosciences.
The Phase III, randomized, double-blind, placebo-controlled study of KINECT-HD, enrolling 128 participants, was designed to evaluate effectiveness Valbenazine as a once-daily treatment for reducing chorea associated with Huntington’s disease, in addition to evaluating the drug’s safety and tolerability. Valbenazine is a selective monoamine transferase 2 (VMAT 2) inhibitor that has not yet been approved by the US Food and Drug Administration. Chorea is an involuntary, erratic movement that is the primary motor feature of Huntington’s disease.
Compared with placebo, valbenazine showed a statistically significant decrease in chorea symptoms and an improvement in overall chorea intensity in patients with Huntington’s disease. Improvement was seen as early as the second week of the study, where participants completed the lowest study dose (40 mg), with consistently greater improvement compared to placebo at all subsequent visits, where the dose was adjusted at intervals. By the end of the 12-week trial, 82% of the participants treated with valbenazine were taking 80 mg.
Notably, KINECT-HD was the first time that the Huntington’s disease health index (HD-HI) had been implemented in a phase III trial. The HD-HI is a patient-reported outcome measure designed to assess clinically meaningful changes in Huntington’s disease function in response to therapeutic interventions. Patients treated with valbenazine reported an improvement in movement and hand/arm function, as well as a decrease in the burden caused by abnormal movements, compared to patients given placebo.
“We are very grateful to the participants and sponsoring partners for their dedication to this study,” said Foer-Stimming.
In December 2022, biopharmaceutical company Neurocrine Biosciences submitted an additional new drug application to the Food and Drug Administration (FDA) for valbenazine as a treatment for chorea associated with Huntington’s disease. The organization is expected to respond to the submission by August 20, 2023. The results of this study are included in the filing.
Huntington’s disease is a rare genetic disease that usually begins in the 30s or 40s, causing the breakdown of nerve cells in the brain over time. About 40,000 people living in the United States are affected by this fatal disease, while another 200,000 are at risk of inheriting the disease. There is no cure, but medications and physical, speech, and occupational therapy can help manage symptoms.
KINECT-HD was conducted by the Huntington Study Group, a global not-for-profit organization, together with its wholly-owned for-profit subsidiary, HSG Clinical Research, Inc. , and in collaboration with the Clinical Trials Coordination Center at the University of Rochester Medical Center for Health + Technology, with funding from Neurobiological Sciences.
Steaming, E.F., et al. (2023) Safety and efficacy of valbenazine for the treatment of chorea associated with Huntington’s disease (KINECT-HD): a phase 3, randomized, double-blind, placebo-controlled trial. Lancet Neuroscience. doi.org/10.1016/S1474-4422(23)00127-8.