10/22/2026
FDA Grants Accelerated Approval for New Breast Cancer Treatment
The U.S. Food and Drug Administration (FDA) has granted accelerated approval to a new treatment for adult patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, locally advanced or metastatic breast cancer upon detection of estrogen receptor-1 (ESR1) mutation during aromatase inhibitor and CDK 4/6 inhibitor therapy, based on an FDA-authorized test. Camizestrant (Etcamah) is an estrogen receptor antagonist administered as an oral tablet.
The safety and efficacy of camizestrant (Etcamah) were evaluated in adult patients with ER-positive, HER2-negative, locally advanced or metastatic breast cancer with detectable ESR1 mutations in SERENA-6 (NCT04964934), a randomized, double-blind, placebo-controlled, multicenter, ctDNA-guided trial to assess the switching to ETCAMAH in combination with a CDK4/6 inhibitor (abemaciclib, palbociclib, or ribociclib) versus continuing aromatase inhibitor (AI) (anastrozole or letrozole) in combination with a CDK4/6 inhibitor. The primary efficacy outcome measure was investigator-assessed progression-free survival (PFS) per RECIST v1.1. An additional efficacy outcome measure included overall survival (OS).
Warnings and precautions for camizestrant (Etcamah) include a Black Box warning for arrhythmia risk with concomitant use of QTc interval-prolonging drugs. Other warnings include bradycardia and embryo-fetal toxicity. The most common adverse reactions (≥ 20%) for camizestrant (Etcamah) include laboratory abnormalities, with camizestrant (Etcamah) in combination with a CDK4/6 inhibitor were decreased neutrophils, decreased leukocytes, decreased hemoglobin, decreased lymphocytes, decreased platelets, visual disturbances, and fatigue.
View the FDA’s announcement here:
https://www.fda.gov/news-events/press-announcements/fda-grants-accelerated-approval-new-breast-cancer-treatment
