R(-)-mdma compositions and methods of treatment

A method of treating an anxiety disorder in a subject in need thereof, comprising administering to the subject a composition comprising an enantiomerically enriched form of R(−)-3,4-methylenedioxymethamphetamine (R(−)-MDMA), or a pharmaceutically acceptable salt or prodrug thereof,

• wherein the administration provides a R(−)-MDMA Tmax of about 2 hours to about 10 hours and a R(−)-MDMA Cmax of about 150 ng/ml to about 3000 ng/ml following administration.