PI3K Inhibitors in 2026: How a Class Built on Withdrawn Approvals Is Producing Its Strongest Breast Cancer Data Yet

https://www.medscape.com/c99/p10/pi3k-inhibitors-2026-how-class-built-withdrawn-approvals-2026a1000z8a?ecd=mkm_ret_261108_mscpmrk_onc_breast-cancer_mai_etid8874665&uac=148436CN&impID=8874665 Two PI3K inhibitors no longer exist in the United States, and two more survive only with indications stripped away. Copanlisib lost its approval in March 2024 after a required confirmatory trial failed to verify the progression-free survival benefit that had earned it accelerated approval in follicular lymphoma.FDA Umbralisib was pulled from the market entirely in June 2022 after updated trial data showed a possible increased risk of death.FDA Duvelisib's follicular lymphoma indication was voluntarily withdrawn in December 2021, and in July 2024 its label gained a new boxed warning for treatment-related mortality with an explicit instruction against first- or second-line use. Copiktra PI Idelalisib's follicular and small lymphocytic lymphoma indications were withdrawn in January 2022, leaving only a chronic lymphocytic leukemia indication on its label.