Ingrezza (valbenazine; Neurocrine Biosciences, San Diego, CA) may provide more benefit in early treatment of chorea symptoms associated with Huntington disease (HD) than Austedo (deutetrabenazine; Teva Pharmaceuticals, Tel Aviv, Israel), according to results of a study presented at the 2023 International Congress of Parkinson’s Disease and Movement Disorders. Improvements in chorea symptoms were not significantly different for Ingrezza and Austedo at later stages of treatment.

Researchers extracted the Unified Huntington’s Disease Rating Scale (UHDRS) Total Maximum Chorea (TMC) scores from the KINECT-HD (NCT04102579) and the First-HD (NCT01795859) clinical trials comparing Ingrezza vs placebo and Austedo vs placebo, respectively. Details about the clinical trials’ methods follow.

KINECT-HD:

• Phase 3, randomized, double-blind, placebo-controlled study
• Included 128 adult participants aged 18 to 75 years
• Participants received 1 single-capsule dose of Ingrezza (30 mg or 40 mg) or placebo daily
• Primary outcome was change from baseline in UHDRS TMC score
• Target dose was 80 mg

First-HD:

• Phase 3, randomized, double-blind, placebo-controlled study
• Included 90 adult participants aged 18 and older
• Participants received Austedo tablets (6 mg, 9 mg, or 12 mg) twice daily, with dose escalated at increments of 6 mg
• Primary outcome was change from baseline in UHDRS TMC score
• Target dose was 48 mg

Researchers conducted an indirect treatment comparison (ITC) at weeks 2, 4, and 6 and at maintenance using the Bucher method. In the early stages of treatment (weeks 2 and 4), Ingrezza yielded greater changes in TMC score from baseline. At weeks 6 and beyond, after dosing for Austedo had escalated, results of an analysis of TMC score changes still favored Ingrezza, however the trend did not reach statistical significance. The results suggest that Ingrezza may be better than Austedo at reducing chorea within a 4-week timespan.

The study authors are affiliated with Neurocrine Biosciences, the John P. and Katherine G. McGovern Medical School, Novel Health Strategies, and the Huntington Study Group.