The Promise of Therapeutic Psilocybin: An Evaluation of the 134 Clinical Trials, 54 Potential Indications, and 0 Marketing Approvals on ClinicalTrials.gov

Introduction: Psilocybin, a tryptamine psychedelic, has been touted in the media both historically and recently as a potential game-changing mental health therapeutic. ClinicalTrials.gov has over one hundred and thirty psilocybin clinical trials listed covering the last twenty years. The single most important aspect of any therapeutic is to gain approval for marketing and thus enter the real-world phase of development. A typical new chemical entity progresses from inception to US Food and Drug Administration (FDA) approval in approximately 12 years and seeks approval for a single indication. Methods: An observational study was conducted with the available information on the ClinicalTrials.gov site to observe the extent of progress made demonstrating the clinical utility of psilocybin. Results: The results showed 134 psilocybin trials typically unblinded studies of 10-20 participants, recruited over years at a single site. Additionally, there have been only three advanced trials (1 Phase 2/3 and 2 Phase 3) submitted, and only in the last two years. Discussion: The hundreds of psilocybin clinical trials initiated over the past twenty years comprising a myriad of potential indications may actually be slowing this potential game-changing mental health therapeutic agent's approval and is costing excessive amounts of capital. To fully evaluate the actual potential of psilocybin, purposeful clinical trials need to be designed well, executed efficiently, and analyzed utilizing sequential and statistically valid processes for each potential indication. This will require a change from the current exploratory forays to defined, well-funded, sequential pharmaceutical development practices, including adequate and appropriate blinding of studies, statistical design to determine the number of participants and more importantly, professional expertise in conducting multicenter trials. Unfortunately, these results demonstrate little real progress towards FDA approval of psilocybin and a field with no clear direction forward.