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Pfizer Announces Positive Topline Phase 2 Results for Next-Generation CDK4 Inhibitor, Atirmociclib, in Second-Line Metastatic Breast Cancer
NEW YORK, March 17, 2026--Pfizer Inc. (NYSE: PFE) today announced positive topline results from the randomized Phase 2 FOURLIGHT-1 study evaluating atirmociclib in combination with fulvestrant, versus fulvestrant or everolimus plus exemestane, in people with hormone receptor (HR)-positive, human epidermal growth factor receptor 2-negative (HER2-) advanced or metastatic breast cancer (MBC) who had received prior cyclin-dependent kinase (CDK) 4/6 inhibitor-based treatment. The study met its primar
About this update from Pfizer, Inc.
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