A Portuguese study on ketamine-assisted psychotherapy, involving 98 patients with treatment-resistant depression, suggests the substance is safe when used in a supervised clinical setting. According to Paulo Cleto Duarte of the Clinic of Change, the treatment showed no unexpected adverse effects and maintained a well-established safety profile. The findings, which will be presented in Lisbon, were validated by international experts David Nutt and Celia Morgan. The study reported clinically relevant reductions in depression, anxiety, and functional impairment, with consistent results observed in follow-ups up to 12 months after the ten-session treatment program.