Researchers are on a fast track to developing a treatment for depression using the psychedelic psilocybin, best known as “magic mushrooms.” The U.S. Food and Drug Administration (FDA) recently gave “breakthrough therapy” designation to a psilocybin-based drug being tested by COMPASS Pathways.

That means an accelerated research and approval process for a drug with strong evidence showing it would be a substantial improvement over currently available therapies and medicines.

“The early studies have shown that psilocybin therapy can provide an immediate and sustained reduction in depression following a single treatment,” Tracy Cheung, communications director for COMPASS Pathways, told Healthline. “The effect has been described as psilocybin shaking the brain up like a snow globe, or rebooting the brain, providing new connections and deactivating connections that might have caused depression.”

COMPASS Pathways is running the first large-scale psilocybin therapy clinical trial for treatment-resistant depression. The study will take place in Europe and North America over the next year or so. More and more researchers are finding evidence that the active ingredient in magic mushrooms, called psilocybin, may have health benefits for a variety of mental health conditions.

In fact, psilocybin was actually widely studied in the 1960s and used in certain therapies before being labelled as a Schedule I illicit drug by the Drug Enforcement Administration (DEA) in 1970.

“The FDA will be working closely with us to expedite the development process and increase the chances of getting this treatment to people suffering with depression as quickly as possible,” said George Goldsmith, COMPASS Pathways chairman and co-founder, in a statement.

The 400-plus patients enrolled in the study will receive synthesized psilocybin capsules, not mushrooms. The clinical trial will take 12 to 18 months to complete. The life sciences company is working with the Heffter Research Institute, which funded the first research into using psilocybin to treat depression at Johns Hopkins University, New York University, and the University of California Los Angeles (UCLA).

Psilocybin mushrooms have been part of religious rituals for thousands of years. The Aztecs of Mexico referred to the mushroom as teonanácatl, or “God’s flesh”, in homage to its believed sacred power. In 1957, Albert Hoffman, a Swiss chemist working for the pharmaceutical company Sandoz, isolated psilocybin from the mushroom.

Fifteen years earlier, he had accidentally ingested LSD, left work feeling dizzy, and experienced its psychedelic effects when he got home. During the 1960s, Sandoz sold psilocybin and LSD for research in medical trials, but the substances were soon outlawed after they became associated with the 60s counterculture. If the new wave of research is successful, it may lead to a change in psilocybin’s reputation after decades of prohibition.