The main ingredient found in the illicit party drug ecstasy could soon become prescription medicine to treat Post-Traumatic Stress Disorder (PTSD).

The US Food and Drug Administration (FDA) this week determined Methylenedioxymethamphetamine (MDMA) to be a “breakthrough therapy” for the disease, with the approval of a phase-three clinical trial – the final stage of research before it can be considered a prescription drug.

It comes after years of research and several clinical trials by the Multidisciplinary Association for Psychedelic Studies (MAPS) found the drug could help sufferers confront their trauma.

But how does the drug help PTSD sufferers, what have the trials found and what does it mean for Australian victims?

According to Psychedelic Research in Science and Medicine president Martin Williams, the results were “too compelling” for the FDA to ignore.

“It’s the Breakthrough Therapy Designation which is the really excellent result at this particular juncture, the results we’ve known from the several trials completed have been excellent in anybody’s language,” Dr Williams told The New Daily.

“But the fact that the FDA is considering Breakthrough Designation suggests that although the number of participants in each of the individual trials around the US other parts of the world were quite small, the results were compelling.”

In pilot trials conducted with 780 human subjects from the US, Israel and Canada, 83 per cent of participants were no longer diagnosed with PTSD after two eight-hour sessions of MDMA-assisted psychotherapy, two months after the treatment.

While in the phase-two trials with 107 participants, 61 per cent had been cleared two months after the three-session study, and another seven per cent at the 12-month follow up.

Phase-three trials will be conducted in late 2018 and aims to be approved by 2021.

How does MDMA work in relation to PTSD?

Unlike partygoers, MDMA for PTSD victims is used as part of psychotherapy treatment and is taken at a significantly lower dose.

According to MAPS and Dr Williams, the drug reduces fear and instills a deep sense of trust in users – the perfect conditions for trauma therapy.

“MDMA is pretty much considered a unique drug in that it has a number of psychological and physiological effects in a user at moderate doses in a clinical setting,” he said.

The clinical trial aims to achieve approval by 2021. Photo: Getty

“The key features of the effects on MDMA are the increase in the trust between the participants or patients and the therapist, so that bond or that trust is really fundamental to the efficacy of the psychotherapy.

“It also opens up a window of calmness and opportunity for the therapist to develop in the patient a condition whereby they can go through a form of exposure therapy, so they are encouraged to relive or to remember some of the aspects of the traumatic incidents.

“Normally without MDMA onboard the anxiety, the tension and the panic can build up to such a level that it becomes overwhelming and the patient isn’t able to go through the process.

“The MDMA enables them to review the traumatic event with a sense of distance and a general warmth and a greater capacity to put the experience in a broader perspective of their lives.”

What does it mean for Australian PTSD sufferers?

Dr Williams, who tried to establish a similar study in Australia, said the possibility of Australian trials hinge on the approval of MDMA in the US.

But if it is approved, the treatment will “almost certainly” be available in Australia “two to four” years after.

“It’s probable in Australia that we would be required to undertake some sort of clinical trial before approval.

”That process would be facilitated by the phase-three trials underway already because clearly the safety and efficacy of the MDMA-assisted psychotherapy has already been established and demonstrated amply in the clinical trials to date.”