Phase 2 Trial Seeks Patients to Test SAGE-718’s Effects on Cognition
The Phase 2 study, called DIMENSION (NCT05107128), is seeking participants in select regions of the U.S. with additional sites in the U.S., U.K., Canada, and Australia expected to open later this year.
DIMENSION is open to adults ages 25 to 65 who have genetically confirmed Huntington’s that is in pre-manifest or early manifest stages, as evidenced by a score higher than 6 but less than 13 on the Unified Huntington Disease Rating Scale (UHDRS) measure of total functioning capacity. Participants must have cognitive challenges — such as impaired judgment, forgetfulness, trouble paying attention, and difficulty thinking through complex problems — but must score lower than 26 on the Montreal Cognitive Assessment, a measure of cognitive impairment.
Prospective participants also must have at least 36 CAG repeats and be able to walk (use of assistive devices such as a walker or cane is acceptable). Individuals with features of juvenile Huntington’s are not eligible to participate, nor are those who have received an experimental treatment in a clinical trial in the last six months.
DIMENSION will randomly assign patients to receive SAGE-718 or a placebo, taken by mouth for 84 days. The study’s main goal is to assess the effect of treatment on cognition as measured by the Huntington’s Disease Cognitive Assessment Battery. UHDRS scores and safety outcomes also will be assessed.
In addition, Sage Therapeutics is planning to open two other trials for SAGE-718 this year. One, called SURVEYOR, will examine the effect of the treatment on real-world functioning in Huntington’s patients. Participants who complete DIMENSION or SURVEYOR can enroll in an open-label extension trial, where all participants will be treated with SAGE-718 and monitored for safety and efficacy outcomes.
The three studies comprise Sage’s PERSPECTIVE clinical trial program to develop SAGE-718.
“The entire Sage team is looking forward to continued work with the [Huntington’s] community and is committed to sharing important information about the SAGE-718 program as it becomes available,” Aaron Koenig, MD, Sage’s vice president of early clinical development, wrote in a letter to the Huntington’s community.
“Participation in a clinical study of any kind is a significant commitment, and we want to extend our immense gratitude to the patients and families who volunteer to participate,” Koenig wrote. “Without you, we would not be able to conduct new research to discover and deliver potentially life-changing medicines to support brain health.”
SAGE-718 is designed to modulate the activity of a nerve protein called the N-methyl-D-aspartate receptor. This protein receptor is important for learning and memory, and its activity is dysregulated in Huntington’s.
The U.S. Food and Drug Administration last year gave SAGE-718 a fast track designation, which aims to speed the development of potential treatments for serious conditions.