4:22 PM PT -- And just like that, the FDA advisers who were mulling over using ecstasy to treat people with PTSD just suggested it ain't happening ... voting against it.

In a 10-1 vote -- with the one person voting for MDMA's use -- the recommendation fell flat ... although the FDA has the final decision. They often run with the committee's vote.

A pharmaceutical version of MDMA, also known as midomafetamine, could become a new treatment for PTSD ... as advisers for the U.S. Food and Drug Administration are considering whether to recommend it for approval.

The panel gathered Tuesday to discuss a treatment developed by Lykos Therapeutics ... which has conducted 2 controlled trials to test how MDMA might help those suffering from PTSD, in addition to therapy.

Of course, MDMA is more widely known as the party drug molly, or ecstasy.

The panel's consideration of the treatment is historic, as Lykos Therapeutics CEO Amy Emerson noted in a statement ... "This will be the first MDMA-assisted therapy and psychedelic-assisted therapy to be reviewed by the Psychopharmacologic Drugs Advisory Committee, a significant milestone in the field of psychedelic medicine, resulting from decades of clinical research and advocacy."

In FDA briefing documents, which were released Friday, Lykos Therapeutics' clinical trial data showed "participants appear to experience rapid, clinically meaningful, durable improvement in their PTSD symptoms."

There are still some concerns, however ... as the drug is known to cause impairment, which could create a risk for the user.

If the drug is approved, the FDA stated safeguards would have to be in place for a future clinical trial -- namely, participants would have to be monitored by 2 therapists over an 8-hour period and would not be allowed to drive until the next day.

The FDA will reportedly make a decision by August 11, since the agency typically follows the rec issued by the advisory panel.

MDMA ... it's not just your kids' molly anymore, potentially.