How important is a secondary endpoint in a pivotal trial? It is worth $490m if you are Myovant Sciences. Yesterday, the group’s shares plunged 26% following relugolix’s failure to show superiority in castration resistance-free survival in metastatic prostate cancer patients. In an additional analysis of the Hero trial 74% of men treated with relugolix were castration resistance-free through 48 weeks versus 75% of those treated with leuprolide, the established androgen-deprivation therapy. Supporters of the stock were quick to point out that this was a secondary endpoint, and that the project had hit its primary endpoint of testosterone suppression in November. However, without a survival benefit – the real gold standard of cancer care – Myovant will almost certainly turn to relugolix’s safety profile and oral administration to show its worth, and the question is whether this is enough. A 50% reduction in MACE events is not to be sniffed at. It should also be remembered that prostate cancer is only forecast to make up 28% of relugolix’s 2026 sales, according to EvaluatePharma, and approval is expected in uterine fibroids and endometriosis. With relugolix still on track for its prostate cancer Pdufa date of December 20 yesterday’s sell-off might look overdone.