Phase III Results Set Neurocrine Up for Huntington’s Chorea sNDA

 

Neurocrine Biosciences announced positive results Friday from its Phase III KINECT-HD study evaluating the efficacy of valbenazine in the treatment of chorea associated with Huntington’s Disease (HD). The data is slated to be presented on April 5th, 2022, during the Emerging Science Session at the American Academy of Neurology 2022 annual meeting.

Huntington’s Disease is a fatal, genetic brain disease caused by a DNA error in a gene called huntingtin. Huntingtin protein is very large and has many functions, but the DNA error in people with HD causes the protein to aggregate in protein clumps in brain cells which cause them to become damaged and die. As HD progresses, symptoms can include personality changes, forgetfulness, unsteady gait, involuntary movements and difficulty swallowing.

Uncontrolled and involuntary movements are also known as chorea, a hallmark symptom of HD due to excessive damage to the part of the brain known as the striatum, which is especially vulnerable in Huntington’s patients. Chorea causes patients to lose weight and have difficulty walking and moving around safely, which leads to a need for around-the-clock care as the disease worsens. 

It is estimated that there are 41,000 Americans with symptomatic HD and another 200,000 who are at-risk of inheriting the disease.

There are currently no approved treatments to prevent the disease’s progression, but Neurocrine aims to make a difference by providing treatment that targets chorea. The KINECT-HD evaluated the use of valbenazine in 128 adults with motor manifest HD. Valbenazine was taken once daily and met its primary endpoint of change in chorea severity and was significantly more effective at improving chorea severity than placebo.       

Treatment with valbenazine also met secondary endpoints of improvement on clinician assessment of how much patients’ illness improved with treatment as well as patient assessment of improvement. The drug also provided improvements in symptoms of chorea as early as week two of treatment, with an upward trend of continued improvement as the trial continued. 

Adverse events reported during the trial were reported to be mild to moderate and consistent with the known safety profile for valbenazine. Side effects included fatigue, fall, excessive sleepiness and akathisia or restlessness.       

Valbenazine is a drug used to treat tardive dyskinesia, a disorder that affects the nervous system and causes repetitive, involuntary muscle movements in the face, neck, arms and legs. It is a vesicular monoamine transporter 2 (VMAT2) inhibitor that changes the activity of certain neural substances in the brain by depleting neuroactive peptides, such as dopamine, at nerve terminals. Depletion of these substances can help decrease spontaneous motor movements associated with chorea and other degenerative neurological conditions.           

“Presentation of these positive data of valbenazine for chorea in Huntington’s disease represent a major step forward in our commitment to offering the community a potential new treatment option,” said Eiry W. Roberts, M.D., chief medical officer at Neurocrine Biosciences. “We are proud to work with the Huntington Study Group and the Clinical Trials Coordination Center at the University of Rochester on this program. Data from the KINECT-HD and the ongoing KINECT-HD2 study will form the basis of our supplemental new drug application (sNDA) for submission to the U.S. Food and Drug Administration later this year.”          

KINECT-HD2 is an open-label Phase III study intended to evaluate the long-term safety and tolerability in the treatment of chorea in HD patients. Neurocrine plans to enroll 150 patients in a 112-week study to collect longitudinal data.