Double-blind, placebo-controlled crossover trial (n=24) testing the role of the 5-HT2a receptor in MDMA-induced effects on social behaviour (MDMA 75 mg; ketanserin 40 mg; combination; placebo).
Randomised, double-blind, placebo-controlled within-subject crossover with four test days (minimum 7-day washout) comparing MDMA 75 mg, ketanserin 40 mg, the combination, and placebo in healthy volunteers.
Primary outcomes assess cognitive and affective empathy measures and tasks; secondary outcomes include social interaction and attitude tasks, memory, and drug and hormone concentrations in blood. Total participant burden approximately 18 hours over a minimum of 5 weeks.
Within-subject crossover with four conditions: MDMA 75 mg; ketanserin 40 mg; MDMA 75 mg + ketanserin 40 mg; placebo.
MDMA 75 mg capsule
Ketanserin 40 mg capsule (active comparator) — given alone or before MDMA in combination condition
Matching placebo capsule