Harmony Biosciences said its experimental drug ZYN002, a synthetic cannabidiol gel,
failed
a Phase 3 study in people with fragile X syndrome, which affects a small subset of people with autism and intellectual disabilities.
Fragile X is characterized by developmental delays, anxiety, learning disabilities and other effects, and the trial’s primary endpoint looked at whether patients improved on a measure of social avoidance. The company cited a “higher than expected” response to placebo to explain the failure.
The late-stage flop marks another setback for the fragile X community, which has no FDA-approved treatments, and it puts a dent in Harmony’s
$60 million deal for Zynerba Pharmaceuticals
that brought the drug in-house.
The 2023
deal
came with the potential for another $140 million in contingent value rights, dependent upon certain Phase 3 milestones and FDA approvals, though that’s up in the air with the trial failure.
Harmony’s stock price
$HRMY
was down as much as 10% in early trading. Analysts at Mizuho had predicted a 60% probability of success in a preview note to clients earlier this month, and had modeled peak potential sales of more than $500 million.
“Although the study did not achieve its primary endpoint, the findings from this study provide valuable insights into fragile X syndrome,” Harmony chief medical officer Kumar Budur said in a press release.
Budur said the company will continue analyzing the data to “better understand the results as part of our continued commitment to the fragile X community.” Other companies have tried in the fragile X space, including
Ovid Therapeutics
, Novartis and Lysogene.
The neurodevelopmental condition impacts about 1% of people with autism and intellectual disabilities worldwide, according to Servier, which just
acquired an experimental fragile X drug
from Kaerus Bioscience earlier this month. The French pharma will pay up to $450 million for Kaerus’ oral small molecule, which will enter Phase 2 next year.