New Kinect-HD Data on Ingrezza

The post-hoc analysis was presented at the Neuroscience Advanced Practice Provider Symposium hosted by the American Association of Neuroscience Nurses in New Orleans.

"This analysis reinforces the primary study findings, showing the consistent benefit of Ingrezza in reducing the involuntary movements of chorea that can affect any part of the body," said Eiry W. Roberts, M.D., Chief Medical Officer, Neurocrine Biosciences. "Notably, the most significant improvements were seen in the arms and legs, which were the most severely affected at baseline. These results are meaningful because they show how Ingrezza alleviates chorea symptoms and therefore helps people with Huntington's disease in their everyday lives."

In the 12-week, Phase III KINECT-HD clinical trial, once-daily Ingrezza demonstrated a significant reduction in chorea severity, as measured by the Unified Huntington's Disease Rating Scale (UHDRS) Total Maximal Chorea (TMC) score, which measures chorea in seven body regions (face, buccal-oral-lingual region, trunk, right and left upper extremities, right and left lower extremities). This post-hoc analysis was conducted to assess the effect of Ingrezza on chorea by individual body region.

In the KINECT-HD study, patients were randomized 1:1 to receive Ingrezza (n=64) at doses of 40 mg, 60 mg or 80 mg, or placebo (n=61). TMC scores at baseline were similar between treatment groups. Key findings from the post-hoc analysis include: i) More participants had potentially meaningful chorea improvements (a TMC score shift from ≥2 at screening/baseline to ≤1 at maintenance) with Ingrezza versus placebo for all affected body regions. ii) Statistically significant chorea improvements were observed for the upper and lower extremities (P<0.05 for each) – body regions with the highest chorea severity seen at baseline. iii) Average TMC body region scores improved at maintenance, with numerically greater improvements for all TMC items with Ingrezza versus placebo.

KINECT-HD was a Phase III, randomized, double-blind, placebo-controlled study designed to evaluate the efficacy of valbenazine as a once-daily treatment to reduce chorea associated with Huntington's disease (HD) and evaluate the safety and tolerability of valbenazine in patients with HD. The study enrolled 128 adults 18 to 75 years of age who were diagnosed with motor-manifest HD and who had sufficient chorea symptoms to meet study protocol criteria. KINECT-HD used the Unified Huntington's Disease Rating Scale (UHDRS) Total Maximal Chorea (TMC) score as the primary efficacy endpoint. The secondary endpoints included Clinical Global Impression of Change (CGI-C) response status and Patient Global Impression of Change (PGI-C) response status for valbenazine treatment. Treatment with valbenazine resulted in a placebo-adjusted mean reduction in the TMC score of 3.2 units (P<0.0001), indicating a substantial improvement in chorea. Secondary endpoints of CGI-C response status and PGI-C response status were also statistically significant and supported the improvements in TMC score that were seen over the 12-week study period. Treatment-emergent adverse events in this study were generally consistent with the known safety profile of valbenazine. The most common adverse reactions in patients with HD included somnolence and sedation, urticaria, rash and insomnia.

View the complete study results from the Phase III KINECT-HD study published in The Lancet Neurology online edition.

Citation: "Safety and efficacy of valbenazine for the treatment of chorea associated with Huntington's disease (KINECT-HD): a phase III, randomised, double-blind, placebo-controlled trial". Authors: Prof Erin Furr Stimming, MD ∙ Daniel O Claassen, MDb ∙ Elise Kayson, MS et al. The Lancet Neurology - Volume 22, Issue 6 p494-504 June 2023