Looks like MDMA is headed for FDA approval - https://www.maps.org/news/media/6786-press-release-fda-grants-breakthrough-therapy-designation-for-mdma-assisted-psychotherapy-for-ptsd,-agrees-on-special-protocol-assessment-for-phase-3-trials
At the end of this video - he makes reference to the results of this study. Brain imaging suggests using MDMA has a similar effect on the brain to pre-tinnitus patients.