There have been a -lot- [0] of MDMA studies at this point, for PTSD and other issues. In particular a common finding is that the efficacy of MDMA+Therapy 1 year post-treatment is far higher than therapy alone (significant reduction in relapse of symptoms as well as severity of symptoms). I encourage you to look at the variety of studies conducted and their different designs and controls and not base your judgement on a single study (this is good advice for any medical research, not only MDMA, as well).