The FDA issued a complete response letter regarding Lykos’ drug application for its midomafetamine capsules, an MDMA-based treatment designed for adults with PTSD. The agency, in a statement released on Friday afternoon, requested an additional Phase 3 trial to better assess the drug’s safety and efficacy.
Amy Emerson, CEO of Lykos, expressed her deep disappointment in the FDA’s decision, highlighting the impact on the millions of Americans suffering from PTSD who have seen no new treatment options for over 20 years. Emerson remarked, “Although another Phase 3 study would extend the timeline by several years, we believe that many of the concerns previously discussed with the FDA, as well as those raised during the Advisory Committee meeting, could be addressed with existing data, post-approval requirements, or by referencing scientific literature.”
The rejection comes just days before the FDA’s August 11 deadline for ruling on the application, marking a significant setback for Lykos. The company had been granted Priority Review status in February and had received Breakthrough Therapy designation back in 2017.
Midomafetamine, also known as MDMA, is being explored as a catalyst in psychotherapy for treating PTSD, a condition that affects millions of Americans annually. Lykos’ approach combines the drug with psychological interventions to enhance treatment outcomes.
The FDA’s concerns mirrored those raised during a heated June 4 advisory committee meeting, where panelists overwhelmingly recommended against approval. Key issues included uncertainties about the long-term effectiveness of the treatment and the potential bias from participants who had previously used MDMA.
Despite these concerns, Lykos has consistently argued that the data from its two Phase 3 trials—where 69% of participants no longer met the diagnostic criteria for PTSD following treatment—provides sufficient evidence of the drug’s efficacy and durability, aligning with FDA guidance.
This setback occurs despite recent support from leading researchers in the field. Last month, 23 medical doctors and researchers from prestigious institutions such as Harvard Medical School and the University of California, Berkeley, urged the FDA to approve MDMA therapy for PTSD, citing a critical need for more effective treatments.
The FDA’s decision could have wider implications for the psychedelic medicine industry, as several companies are currently developing treatments based on substances like psilocybin and ketamine to address various mental health conditions.
Currently, PTSD treatments primarily include trauma-focused talk therapy and two FDA-approved antidepressants. However, many patients either do not respond adequately to these treatments or discontinue them prematurely.
Looking ahead, Lykos plans to engage with the FDA to discuss the recommended actions and explore alternative regulatory pathways for approval. The company did not specify a timeline for the additional study or a potential resubmission of the application.