About HD
Huntington’s disease (HD) is an inherited neurodegenerative disease that affects about 100,000 people around the world with an additional ~300,000 individuals at risk (mutation carriers).
The underlying cause of HD is a mutation in the huntingtin gene, which causes neurons in the brain to degenerate. Neurons have increasing stress and lose their ability to communicate with each other, which is manifest in functional, motor, cognitive, emotional, and behavioral symptoms.
HD is usually diagnosed between the ages of 30 and 50 and progresses slowly over 15 to 20 years. However, HD can also occur in children and young adults (known as juvenile onset HD or JHD). Patients progressively lose their ability to hold a job, manage their finances, and perform household tasks and/or important activities of daily living, including taking care of themselves.
HD is one of the most devastating neurodegenerative disorders, impacting not only patients but their families as well.
At the present time, there is no treatment to slow progression of the disease. Every child of a parent with HD has a 50/50 chance of inheriting the genetic mutation.
HD is one of the most devastating neurodegenerative disorders, impacting not only patients but their families as well.
At the present time, there is no treatment to slow progression of the disease. Every child of a parent with HD has a 50/50 chance of inheriting the genetic mutation.
Pridopidine has now been submitted for marketing approval for the treatment of Huntington’s disease (HD) in Europe and is in late-stage development for the treatment of HD in the United States and Rest of World.
Prilenia announced in April 2023 preliminary topline results of its Phase 3 PROOF-HD clinical study evaluating the safety and efficacy of pridopidine in individuals with Huntington’s disease (HD).
Preliminary analysis of PROOF-HD indicated that the Phase 3 study did not meet its primary endpoint, change from baseline compared to placebo at 65 weeks, as measured by the Unified Huntington Disease Rating Scale-Total Functional Capacity score (TFC), or the key secondary endpoint, measured by the Composite Unified Huntington’s Disease Rating Scale (cUHDRS). Effects on both of these measures were reduced by the use of concomitant medications.
Pre-specified analyses that excluded participants taking neuroleptics and chorea medications showed clinically meaningful and nominally significant benefits for participants on pridopidine across multiple measures, including disease progression (cUHDRS) and cognition (Stroop Word Reading Test, SWR), at various timepoints. There were also positive trends in motor (TMS) and function (TFC). For many of these measures, this represented improvement from baseline values.
Additionally, important secondary endpoints measuring Q-Motor, a quantitative, objective, rater-bias independent, computerized assessment of motor function, showed robust and nominally significant beneficial effects for participants on pridopidine and improvement from baseline. The effect was further strengthened when excluding participants taking neuroleptics and chorea medications.
Pridopidine was well-tolerated with no serious treatment-related adverse events, with a safety and tolerability profile similar to placebo and consistent with previous clinical studies.
Prilenia holds orphan drug designation for pridopidine in HD in both the United States and EU. In addition, pridopidine has received Fast Track designation by the US Food and Drug Administration (FDA) for the treatment of HD. Drugs that receive Fast Track designation may be eligible for more frequent communications with the FDA and may also qualify for accelerated approval and priority review of new drug applications.
