08:54 AM EDT, 09/24/2025 (MT Newswires) -- Harmony Biosciences ( HRMY ) said Wednesday that its late-stage trial of ZYN002 to treat Fragile X syndrome has missed its primary endpoint.

The company said the drug did not meet the primary endpoint of improving social avoidance primarily due to a higher-than-expected placebo response rate.

Harmony said it will conduct a comprehensive analysis to better understand the results.

Fragile X syndrome is a genetic disorder that causes behavioral symptoms, such as social avoidance and irritability.

Shares of Harmony Biosciences ( HRMY ) were down more than 6% in recent Wednesday premarket activity.