The beleaguered PI3K-delta inhibitor space took another blow after MEI Pharma Inc. and partner Kyowa Kirin Co. Ltd. said the U.S. FDA won’t greenlight zandelisib without data from a randomized study. The firms had hoped to win accelerated approval in relapsed/refractory follicular lymphoma and marginal zone lymphoma based on a single-arm phase II study called Tidal.