Analysts Call Huntington's Trial 'Underwhelming' as Sage Fails to Prove Dalzanemdor's Efficacy

Sage Therapeutics’ dalzanemdor faces scrutiny as it navigates trials aimed at treating neurodegenerative diseases, with a particular focus on Huntington's disease. Investors eagerly await the phase 2 DIMENSION study results to determine the drug's efficacy.

The latest data from the phase 2 SURVEYOR study raised questions about dalzanemdor's ability to improve cognitive function in Huntington's disease patients. This study's primary objective was to discern cognitive differences between 40 Huntington's patients and 29 healthy participants using the HD-Cognitive Assessment Battery (HD-CAB). The findings revealed only a "small numerical difference" between the drug and placebo groups, leading analysts to deem the results as "underwhelming."

Sage has positioned dalzanemdor for four midstage trials targeting Alzheimer’s, Huntington’s, and Parkinson’s diseases, all expected to report results this year. The preceding trial in Parkinson's, the PRECEDENT study, did not showcase improvements in cognitive performance, adding to the skepticism surrounding dalzanemdor's potential.

In the SURVEYOR study, following the initial cognitive assessment, Huntington’s patients were given either dalzanemdor or a placebo for 28 days. Despite some signs of directionally positive effects in individual HD-CAB tests and functional assessments, the overall impact was minimal. Nevertheless, Sage emphasized that the drug was generally well tolerated, with most adverse events being mild to moderate.

Despite these safety assurances, the lackluster efficacy results have left analysts cautious. William Blair analysts highlighted that while there was a slight numerical change in HD-CAB scores between the dalzanemdor and placebo groups, it was not significant enough to be conclusive.

The tepid response from the market is reflected in Sage's stock price, which stayed relatively stable at around $10.90 in premarket trading following the announcement. This muted reaction underscores the uncertainty surrounding dalzanemdor's future prospects.

Dr. Laura Gault, Sage's Chief Medical Officer, noted the importance of recognizing cognitive impairment in Huntington's disease, an aspect often overshadowed by motor symptoms. She emphasized that the SURVEYOR study contributes to a better understanding of the cognitive challenges associated with Huntington's, an area with no currently approved treatments.

As Sage continues to pursue its plans for dalzanemdor in Huntington's and Alzheimer's diseases, the upcoming results from the DIMENSION and LIGHTWAVE trials will be crucial. The biotech has already decided to discontinue its efforts in Parkinson’s disease following the disappointing PRECEDENT study results.

In summary, dalzanemdor’s journey is marked by cautious optimism and significant challenges. The phase 2 SURVEYOR study offered some insights but fell short of demonstrating substantial cognitive benefits for Huntington's disease patients. The forthcoming DIMENSION study results are eagerly awaited as they will play a pivotal role in determining the drug's fate in Sage's pipeline and its potential as a treatment for Huntington's disease.