Dear Huntington’s Disease Advocacy Community,

Today, Sage Therapeutics announced topline results from the Phase 2 SURVEYOR Study. SURVEYOR was a small learning study with three objectives: to determine the magnitude of cognitive impairment in participants with HD compared to healthy participants, to evaluate the safety of dalzanemdor in participants with HD, and to better understand the relationship between changes in cognition and changes in function.

The study met its primary endpoint demonstrating a statistically significant difference as measured by the HD-Cognitive Assessment Battery (HD-CAB) composite score at baseline between healthy participants and participants with Huntington’s Disease (HD) prior to any treatment with dalzanemdor (SAGE-718) or placebo.

The baseline composite score for participants with HD was markedly lower compared to healthy participants, further underscoring the extent of cognitive impairment associated with HD and the significant unmet need for treatment options. We hope these findings will help contribute to a greater understanding and urgency to address cognitive impairment associated with HD.

The secondary safety endpoint showed that dalzanemdor was generally well-tolerated, and there were no new safety signals observed.

For further information, please see the press release. 

Based on these results, Sage is continuing to evaluate the SURVEYOR Study data and will apply relevant learnings to our ongoing work on the dalzanemdor program.

We would like to acknowledge the meaningful contributions of everyone who made this research possible. Sage is immensely grateful for the time and role played by study participants, family members, care partners, and advocates. We look forward to sharing future updates with the Huntington’s disease community as they become available.

Please be in touch if you have any questions. We look forward to our continued conversation.

With gratitude,

Lesley White, MSW, LICSW Director, Pipeline Patient Engagement & Advocacy