Preparatory work to establish the PATHWAYS clinical trial on the prescription of puberty blockers for children and young people with gender incongruence has been paused after the Medicines and Healthcare products Regulatory Agency (MHRA) raised new concerns. The Department of Health and Social Care (DHSC) said recruitment will not begin until the regulator’s issues are resolved with the sponsor and trial clinicians.
King's College London, the trial sponsor, is scheduled to begin discussions with the MHRA next week to address the points raised. Until that dialogue concludes, the study will remain in set‑up pause rather than moving into participant enrolment.
The study was intended to evaluate the use of puberty blockers-gonadotrophin‑releasing hormone (GnRH) analogues-within a research protocol for children and young people with gender incongruence. DHSC confirmed that no participants will be recruited until the regulator and clinical leaders are satisfied with the safeguards and evidence base.
According to DHSC, the Government’s position is unchanged: the safety and wellbeing of children and young people are the red lines for any research of this type. Officials said the trial will proceed only if expert scientific and clinical advice determines it is both safe and necessary.
MHRA indicated its latest concerns relate directly to participant wellbeing, prompting further scientific review before any medicines are prescribed within the study setting. This reflects the regulator’s oversight role for trials involving investigational medicinal products and its ability to require changes before recruitment starts.
The pause concerns the research programme rather than routine clinical services. In practical terms, there will be no recruitment or prescribing under the trial protocol while the sponsor addresses the regulator’s queries, updates documentation if needed, and demonstrates that participant protections meet the required threshold.
For research teams preparing to support PATHWAYS, the immediate effect is a delay to site activation and screening activities. Families who had anticipated referral routes into the study will now wait for the outcome of the MHRA–sponsor dialogue and any subsequent communications from clinical leaders.
No revised timetable has been set. The next formal step is the MHRA–King's College London discussion, after which the sponsor will confirm whether amendments are required and whether conditions for commencing recruitment have been met. DHSC reiterated that children’s safety and wellbeing will continue to drive decision‑making.