An independent advisory committee voted against approval of MDMA for PTSD. This makes it unlikely the FDA will approve it, but we’re still not sure. There’s no reason to believe this substantially affects the opportunity for other psychedelics to be approved for other psychiatric conditions.
On May 30, 2024, there were headlines everywhere (at least everywhere this Nerdy Girl looked!) about the vote against MDMA for PTSD by an FDA scientific advisory panel. The panel voted 9-2 that the data do not show that MDMA is effective in counteracting symptoms of PTSD and 10-1 that the benefits do not outweigh the risks of taking the drug for this purpose. Just a side bar about these committees. The FDA has about 50 advisory committees, which include both scientific experts and members of the public, usually including a consumer representative, an industry representative, and a patient representative. The FDA is not obligated to listen to the advisory panel, but they usually follow their advice about ⅔ of the time.
In this case, the advisory committee had 2 types of criticisms about the studies conducted by Lykos Therapeutics about MDMA for PTSD: (1) methodological and (2) safety-related. On the methodological side (meaning how the studies were done), the advisory committee noted 2 things that they felt called into question whether or not this drug really works to alleviate symptoms of PTSD:
- Both patients and therapists in the study were basically unblinded. While people weren’t told whether they got MDMA or placebo, it’s fairly easy for people to tell whether they’ve taken MDMA or not, as the short-term effects are quite dramatic! The gold standard in drug trials is “double blinding,” which basically means no one involved knows who got the drug and who didn’t. If you know you got the drug, it can affect your response if, for example, you think you should be feeling better. It might make you answer survey questions more positively or behave differently in ways that will affect the overall outcomes of the trial.
- The sample size was too small. The advisory committee noted that there were only 200 people in the phase 3 trials.
Now on to the safety concerns. There were 3 main concerns about safety:
- The study didn’t look at potential for abuse of MDMA. There is a concern that the drug can be addictive, and the study didn’t look into this at all. The advisory committee felt that there needed to be more information about the risks of abuse to know whether the benefits outweighed the risks.
- 40% of the people in the trial had previous experience with MDMA. The advisory committee worried that the sample was skewed toward people who didn’t have bad reactions to the drug, and that’s why they enrolled in the study. This could skew the safety results if there was some reason why some people are safe from bad outcomes while others aren’t, all the while not allowing us to see how widespread bad outcomes might be in a more general population.
- In some cases, there were considerable increases in blood pressure and heart rate that could lead to poor cardiovascular outcomes. This concern was largely unresolved in the discussion and gave the advisory committee pause.
Putting aside the specifics of the committee’s deliberations, the general public conversation about this is disheartening. There hasn’t been a new therapeutic for PTSD approved in over 20 years. Thankfully, public pressure is ramping up for something to be done. At the same time, many people are wondering whether this vote has implications for other psychedelics that are currently being researched for treatment of psychiatric conditions, such as psilocybin for treatment resistant depression. In the case of these tough-to-treat disorders like PTSD and treatment-resistant depression that often do not respond well to existing medications, the prospect of psychedelic therapy offers great hope. I think there is reason to hold on to optimism here. Even if the FDA votes against MDMA, this process has been a learning experience for those in the industry. This Nerdy Girl still thinks psychedelics have a future in the treatment landscape and is grateful for all the scientists who are working on new therapies for this set of highly complex and at times devastating illnesses.
Additional Resources:
Phase 3 trial of MDMA for PTSD
Johns Hopkins Center for Psychedelics and Consciousness Research
Icahn School of Medicine Center for Psychedelic Therapy Research
