Harmony Biosciences’ Cannabidiol Therapy Misses Phase III Endpoint in Fragile X Syndrome

Harmony Biosciences’ transdermal cannabidiol, ZYN002, failed to meet the primary endpoint in its pivotal Phase III trial for Fragile X Syndrome (FXS), triggering a 16.6% drop in the company’s share price. The RECONNECT trial (NCT04977986) assessed ZYN002 in patients aged three to 30, measuring changes in the ABC-CFXS Social Avoidance subscale over 18 weeks. Harmony attributed the trial’s failure to a higher-than-expected placebo response and did not release detailed data. The setback casts uncertainty over ZYN002’s market potential, which was acquired from Zynerba Pharmaceuticals in 2023 for up to $200 million. Fragile X, a leading inherited intellectual disability linked to autism, currently has no approved therapies beyond symptom management. Despite this setback, other companies, including Shionogi, Servier, and Spinogenix, are advancing novel therapies for FXS. Harmony emphasized its broader late-stage pipeline, signaling ongoing commitment to developing innovative treatments for neurological disorders.

25-09-2025