In the past year, the U.S. Food and Drug Administration (FDA) approved five treatment options for patients with breast cancer, which are summarized herein.
Abemaciclib Combination
On October 12, 2021, the FDA approved abemaciclib (Verzenio) with endocrine therapy (tamoxifen or an aromatase inhibitor) for the adjuvant treatment of adult patients with hormone receptor–positive, HER2-negative, node-positive early breast cancer.
Neoadjuvant and Adjuvant Pembrolizumab
On July 26, 2021, the FDA approved pembrolizumab (Keytruda) for high-risk, early-stage triple-negative breast cancer in combination with chemotherapy as a neoadjuvant treatment, and then continued as a single agent as adjuvant treatment after surgery.
Neoadjuvant and adjuvant approval was based on the results of the KEYNOTE-522 trial, which investigated the efficacy of pembrolizumab plus neoadjuvant chemotherapy followed by surgery and continued adjuvant treatment with single-agent pembrolizumab in patients with newly diagnosed, previously untreated, high-risk, early-stage triple-negative breast cancer. For more information on the KEYNOTE-522 trial, see here.
Sacituzumab Govitecan-hziy
On April 7, 2021, the FDA granted regular approval to sacituzumab govitecan-hziy (Trodelvy) for patients with unresectable locally advanced or metastatic triple-negative breast cancer who have received two or more prior systemic therapies, at least one of them for metastatic disease.
Efficacy and safety were evaluated in the ASCENT trial conducted in patients with unresectable locally advanced or metastatic triple-negative breast cancer who had relapsed after at least two prior chemotherapies, one of which could be in the neoadjuvant or adjuvant setting, if disease progression occurred within 12 months. Patients were randomly assigned to receive sacituzumab govitecan or physician’s choice of single-agent chemotherapy. For more information on the ASCENT trial, see here.
Margetuximab-cmkb Plus Chemotherapy
On December 16, 2020, the FDA approved margetuximab-cmkb (Margenza) in combination with chemotherapy for the treatment of adult patients with metastatic HER2-positive breast cancer who have received two or more prior anti-HER2 regimens, at least one of which was for metastatic disease.
Efficacy was evaluated in SOPHIA of patients with immunohistochemistry 3+ or in situ hybridization–amplified HER2-positive metastatic breast cancer who had received prior treatment with other anti-HER2 therapies. Patients were randomly assigned to receive margetuximab plus chemotherapy or trastuzumab plus chemotherapy. For more information on the SOPHIA trial, see here.
Pembrolizumab Combination
On November 13, 2020, the FDA granted accelerated approval to pembrolizumab in combination with chemotherapy for the treatment of patients with locally recurrent unresectable or metastatic triple-negative breast cancer whose tumors express PD-L1 (combined positive score [CPS] ≥ 10) as determined by an FDA-approved test. The FDA also approved the PD-L1 IHC 22C3 pharmDx as a companion diagnostic for selecting patients with triple-negative breast cancer for pembrolizumab.
Approval was based on the phase III KEYNOTE-355 study of patients with locally recurrent unresectable or metastatic triple-negative breast cancer, who had not been previously treated with chemotherapy in the metastatic setting. Patients were randomly assigned to receive pembrolizumab or placebo in combination with different chemotherapy treatments (paclitaxel protein-bound, paclitaxel, or gemcitabine plus carboplatin) via intravenous infusion. For more information on the KEYNOTE-355 trial, see here.
