Oct. 30, 2018 -- The long-banned “club drug” MDMA showed strong results as a treatment against posttraumatic stress disorder in its largest and longest study to date, researchers reported Monday.

The phase II clinical trial followed 28 patients with chronic PTSD, including military veterans and crime victims, who took the drug during three daylong psychotherapy sessions over 3 months. After two sessions, 43% of the group that received active doses of MDMA no longer met the definition of PTSD, compared to 33% who got a low dose of the drug as a placebo. And a year after the first session, 76% of the active-dose group no longer had PTSD, according to results published in the Journal of Psychopharmacology.

The long-term results are better than those seen in previous MDMA studies, says Brad Burge, a spokesman for the Multidisciplinary Association for Psychedelic Studies, which funded the research.

“That efficacy actually increases the more time passes,” Burge says. “That’s absolutely remarkable, especially when compared to traditional treatments where people have to take drugs for months or years, or for the rest of their lives, to see any benefit at all.”

Doctors diagnose posttraumatic stress disorder in people who’ve experienced a life-threatening event by looking at a battery of symptoms, including nightmares, flashbacks, or feelings of depression. These new results don’t mean that all the problems associated with participants’ PTSD have gone away, “but they don’t qualify for a diagnosis of PTSD anymore,” Burge says.

MDMA is the active ingredient in what’s commonly known as “ecstasy” or “Molly.” It was invented in 1912 as a way to help produce drugs that controlled bleeding. But starting in the 1970s, psychiatrists found it enhanced communication with patients. By the mid-1980s, it was becoming widely abused, and the U.S. government banned it in 1985.

The latest MDMA study, conducted at a private clinic in Boulder, CO, produced no serious adverse events related to the drug. MDMA can cause the heart to race and blood pressure to jump, but the participants handled the drug well, the researchers report.