The U.S. Food and Drug Administration’s Oncologic Drugs Advisory Committee is holding a meeting on April 21, 2022, to discuss safety findings across the entire class of PI3K inhibitors for hematological cancers. Dysregulated PI3K signaling helps malignant lymphocytes survive and proliferate. The FDA is essentially asking the advisory committee to make a recommendation on whether future approvals for this class of drug should be based on randomized data instead of single-arm clinical trials.

Currently, there are four PI3K inhibitors approved by the FDA under this context. They are Gilead Sciences’ Zydelig (idelalisib), Bayer’s copanlisib, Secura Bio’s develisib, and TG Therapeutics’ umbralisib. A fifth drug, alpelisib, a PI3K alpha-specific inhibitor approved for breast cancer and PIK3CA-related overgrowth spectrum, will not be included in the discussion.

Gilead’s Zydelig is approved for relapsed chronic lymphocytic leukemia (CLL), in combination with rituximab, in patients for whom rituximab alone would be considered appropriate therapy due to other comorbidities. Gilead has since withdrawn the drug from the market for certain types of cancer after failing to complete follow-up clinical trials to confirm efficacy and safety. Read more here.