The US Food and Drug Administration (FDA) has rejected the use of MDMA in therapy in the USA and requires that further studies be conducted before approval.

In the US, MDMA-assisted therapy has been tested for years to treat PTSD. Previous study data show that combining it with therapy can improve mental health.

Data from the third phase of a clinical trial by the US pharmaceutical company Lykos Therapeutics show that 71 percent of the subjects were no longer diagnosed with PTSD after taking the drug therapeutically.

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On August 9, Lykos Therapeutics announced that the FDA had rejected its application to launch MDMA-assisted psychotherapy for PTSD, a major setback.

The FDA called for further studies to test the safety and effectiveness of the trials, which according to Scientific Americancould take years and would require significant resources.

In a statement released by Lykos, the FDA said it had concerns about “lack of data” and the nature of the studies themselves.

“The articles remain scientifically sound and represent important contributions to research into potential treatments for PTSD,” Lykos said in a statement (via The New York Times).

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Lykos announced that the company would appeal the FDA’s decision and also file a complaint with the Committee on Publication Ethics, an organization that sets guidelines for scientific publications.

In conversation with Scientific AmericanJennifer M. Mitchell, a neuroscientist who led the Phase 3 clinical trials, said the rejection was “disappointing.”

“In my opinion, we have met the criteria required by the FDA and I fully stand behind our data,” she said.

(Above Scientific American)

Gemma Ross is Mixmag’s deputy editor. Follow her on Þjórsárdalur