A study to evaluate Sage-718 on cognitive function in participants with Huntington's Disease (H-52090)

A randomized, placebo-controlled, double-blind study to evaluate the effect of Sage-718 on cognitive function in participants with Huntington's Disease

Sage Therapeutics, Inc. is sponsoring this study of an investigational drug called SAGE-718.

SAGE-718 is being evaluated for possible development in several brain disorders, including for the potential treatment of mild cognitive impairment (involving mental activities like thinking, learning, decision-making, and remembering) and dementia. Dementia is a condition in the brain that affects memory, thinking, decision-making, and social abilities, and can disrupt normal daily activities.

N-methyl-D-aspartate (NMDA) receptors are a type of protein with an important role in the ability of nerve cells to communicate with each other. Preliminary data suggest that lowered NMDA receptor tone may contribute to cognitive dysfunction in HD. SAGE-718 is a novel, first-in-class modulator (regulator of activity) of NMDA receptors.

SAGE-718 has previously been studied in healthy volunteers and a small number of subjects with HD. HD is a neurodegenerative disease (a disease that leads to progressive loss of brain function and structure) characterized by specific motor (movement), psychiatric (related to mental illness), and cognitive symptoms. Sage-718 is also currently being studied in people with Parkinson’s disease (PD) and Alzheimer’s disease (AD).

The main purpose of this study is to:

• Evaluate the effect of SAGE-718 on cognitive performance in study subjects with HD

This study will also do the following:

• Evaluate the effect of SAGE-718 on overall functioning and health-related quality of life
• Evaluate the safety and tolerability of SAGE-718
• Evaluate the effect of SAGE-718 on neuropsychiatric symptoms
  • Neuropsychiatric: involving the relationship between your brain and your behavior and how diseases of the brain and central nervous system affect the way you feel, think, and behave
• Evaluate your blood and urine after daily doses of SAGE-718 to see:
  • How your body absorbs, breaks down, and removes SAGE-718 from your body, and
  • How SAGE-718 works inside your body