The FDA is evaluating whether three widely used breast cancer pills, Ibrance (palbociclib), Kisqali (ribociclib), and Verzenio (abemaciclib), may carry a risk of colitis, an inflammation of the large intestine. The drugs, along with the Kisqali Femara Co-Pack, appear on the agency's latest quarterly list of potential safety signals, which covers April through June 2026 and was current as of Sept. 30.
Next to the entry, the FDA wrote: "FDA is evaluating the need for regulatory action." The agency has not concluded that the drugs cause colitis, and it has not told patients to stop taking them.
