On May 26, 2011, the 12th and final subject was treated in MAPS’ Swiss study of LSD-assisted psychotherapy for anxiety associated with advanced-stage illness. Once we collect follow-up data from this subject in July, we will have completed the first clinical LSD study in a patient population in over 35 years, representing a major milestone in the renaissance of psychedelic research. In 30 treatment sessions, not a single subject experienced severe negative reactions (serious adverse events, or SAEs) such as psychotic experiences, suicidal crises, flashbacks, or severe anxieties (bad trips). According to Clinical Investigator Peter Gasser, M.D., all 12 patients reported benefits from the treatment—however, it is too early to say whether the results will be statistically significant. Regardless of statistical significance, however, the preliminary results indicate that the risk of administering LSD in carefully controlled clinical settings is acceptably low, and that there is a promising future for LSD research. You can also read more about the historical significance of this study in David Jay Brown’s May 27 article, “Landmark Clinical LSD Study Nears Completion.”