PERIODS: the first dedicated tirzepatide trial in PCOS is recruiting
Source: ClinicalTrials.gov NCT07326111 (University of Bonn), recruiting since 9 December 2025
Summary
PERIODS (ClinicalTrials.gov NCT07326111) is a phase 4, placebo-controlled trial of tirzepatide in women with overweight or obesity and PCOS-related ovarian dysfunction, sponsored by the University of Bonn. It began recruiting on 9 December 2025 with a planned enrolment of 198 participants; both arms combine the study drug or placebo with lifestyle modification. What makes it notable is the primary outcome: whether menstrual regularity improves — a reproductive endpoint, rather than the weight endpoints that every large tirzepatide trial so far has been built around. It is the first trial designed specifically to answer the PCOS question instead of inferring it from obesity data. Status as of 8 October 2026: recruiting. No results have been published, and none should be expected for some time given the trial's duration.
Why it matters for you
Nothing to act on today — this is the trial to watch. If you read a confident claim online that tirzepatide 'restores cycles in X% of women with PCOS', check what it is based on: as of October 2026 the only randomised cycle data come from one 60-participant, 16-week open-label study, and PERIODS has not reported.