A planned clinical trial examining the use of puberty blockers for transgender adolescents in England has been placed on hold following intervention from the nation’s medicines regulator, adding another layer of uncertainty to youth gender care within the National Health Service.
The study, known as the PATHWAYS trial, was commissioned by the National Health Service to evaluate the effects of puberty-suppressing medication on young people experiencing gender dysphoria. It was expected to recruit more than 200 participants under the age of 16. However, the Medicines and Healthcare Products Regulatory Agency has requested additional safety measures before the research can proceed, effectively pausing the launch.
According to UK media reports, regulators raised concerns about long-term safety data, particularly around bone density, fertility, and neurological development. Officials have asked researchers to review the study’s design, including whether the minimum age for participation should be raised.
The trial was developed in response to recommendations from the Cass Review, an independent review of children’s gender identity services in England. The Cass Review concluded that there was insufficient high-quality evidence supporting the routine prescription of puberty blockers for minors and recommended that such treatments only be provided within formal research settings.
Since 2024, the NHS has restricted new prescriptions of puberty blockers for transgender youth outside of clinical trials. The PATHWAYS study was intended to create a structured research pathway to gather stronger long-term data.
Health Secretary Wes Streeting has previously defended the cautious approach, stating that children’s safety must come first and that treatment decisions should be grounded in robust clinical evidence. The Department of Health has indicated that no participants will be enrolled until regulators are satisfied that safeguards are sufficient.
The trial is being led by researchers affiliated with King’s College London and other NHS partners. Researchers have emphasized that the purpose of the study is to better understand both the benefits and potential risks of puberty suppression, not to predetermine outcomes.
The pause has drawn mixed reactions. Some advocacy groups argue that delaying research further limits access to care for young people already facing long waiting lists and heightened scrutiny. Others maintain that tighter oversight is necessary given the ongoing debate over the long-term impacts of medical interventions during adolescence.
For now, recruitment remains suspended while regulatory discussions continue. NHS officials have stated that youth gender services will continue to operate under current policies, with psychological support and other non-medical interventions available.
The future timeline for the trial’s launch remains unclear. What is certain is that the debate over transgender youth healthcare in the UK remains deeply contested, with research, regulation, and politics intersecting in ways that continue to shape national policy.
