A high-profile clinical trial of drugs that can delay puberty in children questioning their gender can go ahead after the High Court rejected a legal challenge by campaigners. The Pathways trial, run by researchers at King's College London (KCL), will start recruiting more than 220 children aged between 11 and 16 years old from 1 August. The study was commissioned to assess the benefits or risks of puberty blockers, after a landmark review into gender services found the evidence for treating young people with the drugs was "remarkably weak". The judge, Mr Justice Chamberlain, refused the application for a judicial review saying that none of the claims made by the campaigners had a realistic chance of success. Campaigners, including parents of gender-questioning children, said they were disappointed by the decision saying the "world is watching" a case which has "global implications and high stakes".