Pridopidine Phase 3 Study in Huntington's Disease

Condition(s) studied

Investigational drug(s) / intervention(s)

Pridopidine: Pridopidine hard gelatin capsule

Placebo: Matched placebo hard gelatin capsule

Study summary

The goal of this clinical trial is to learn if pridopidine can slow the clinical decline of Huntington's Disease (HD) in adult participants. It will also inform about the safety of pridopidine.

The main questions the study aims to answer are:

Does pridopidine slow the overall worsening of HD over 1 year? Does pridopidine slow the worsening of specific aspects of HD over 1 year, namely the clinical progression, the ability to perform daily life activities (functional capacity), the mind's ability to process information (cognition), working of the muscles (motor function), and quality of life?

Researchers will compare the drug pridopidine to a placebo (a look-alike substance that contains no drug) to see if pridopidine works better than placebo to treat HD. During the first year of the study, participants will have the same chance to receive either pridopidine or placebo.

Participants will:

Take 1 pridopidine or placebo capsule twice daily for 12 months. Visit the clinic 6 times within 1 year for checkups and tests.

All participants who complete this 1-year placebo-controlled study period will roll over into an additional 2-year study period during which all participants will receive pridopidine treatment, including participants who had received placebo during the first year. During this additional 2-year treatment period participants will visit the clinic a total of 6 times for checkups and tests.

Eligibility

Primary outcome measure(s)

• Change in Composite Unified Huntington's Disease Rating Scale (cUHDRS) — Change from Baseline to Week 52
  cUHDRS is a combined score to assess disease progression in HD. It includes TFC, TMS, SDMT, and SWR: Total Functional Capacity (TFC) tests the capacity to maintain daily living, finances, care level, occupation. Higher score = better outcome. Best score=13. Worst score=0. Total Motor Score (TMS) assesses motor features (oculomotor, dysarthria, chorea, dystonia, gait, postural stability). Higher score = worse outcome. Best score=0. Worst score= 124. Stroop Word Reading (SWR) measures attention and mental flexibility. Participant reads names of colors printed in black ink. Scores reflect correct responses in 45 sec. Higher score = better outcome. Best score=100. Worst score=0. Symbol Digit Modalities Test (SDMT) tests psychomotor speed and working memory. Participant has 90 sec to match numbers with symbols. Scores = correct answers in 90 sec. Higher score = better outcome. Best score=120. Worst score=0. Total integrated cUHDRS scale range: -7.6 to 24.8. The higher, the better.

Trial sites (66)

+ 26 more sites — see the full list on the official registry below.