Federal health regulators on Friday declined to approve the as a therapy for PTSD, a major setback for groups seeking a breakthrough decision in favor of using to treat serious mental health conditions. Drugmaker Lykos Therapeutics said the FDA notified the company that the drug “could not be approved based on data submitted to date,” and requested an additional late-stage study. Such studies generally takes several years and millions of dollars to conduct.

The drugmaker said it plans to ask the agency to reconsider. had hoped that MDMA would be approved and pave the way for other . If the FDA had granted the request, MDMA, also known as ecstasy or molly, would have become the first illegal psychedelic to become a federally approved medicine.

The FDA’s decision was expected after a panel of for post-traumatic stress disorder in May. The negative vote came after an all-day meeting in which , research methods and possible risks of the drug, including heart problems, injury and abuse. FDA said Friday the MDMA application had “significant limitations” that “prevent the agency from concluding that the drug is safe and effective for the proposed indication.

” The agency said it will continue encouraging “innovation for psychedelic treatments and other therapies to address these medical needs.” Lykos said the issues FDA raised in what's called a complete response letter echoed the concerns during the May meeting. “The FDA request for another study is deeply disapp.