Drugmaker Lykos Therapeutics announced on Aug. 9, 2024, that the Food and Drug Administration declined to approve the company’s application^[1] for the use of MDMA-assisted therapy in the treatment of post-traumatic stress disorder^[2]. It is the first such decision issued on a psychedelic drug application.

Many investors and researchers have been predicting a psychedelics boom^[3], with MDMA being just the first of a number of...