Pharmacist Medication Insights: Margetuximab for Metastatic HER2-Positive Breast Cancer

Margetuximab-cmkb (Margenza) was approved in December 2020 in combination with chemotherapy for the treatment of adult patients with metastatic HER2-positive breast cancer who have previously received 2 or more anti-HER2 regimens, at least one of which for metastatic disease.

In December 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 previously received 2 or more anti-HER2 regimens, at least one of which for metastatic disease.

The regulatory decision was based on findings from the phase 3 SOPHIA trial (NCT02492711), in which the Fc-engineered monoclonal antibody plus chemotherapy demonstrated a statistically significant reduction in the risk of disease progression or death of 24% vs trastuzumab (Herceptin) in combination with chemotherapy (HR, 0.76; 95% CI, 0.59-0.98; P =.033).

The median PFS with the margetuximab-cmkb regimen was 5.8 months vs 4.9 months with the trastuzumab regimen. Moreover, the objective response rate reported with the margetuximab-cmkb/chemotherapy combination was 22% vs 16% with trastuzumab plus chemotherapy. Data from the final overall survival (OS) analysis of the trial are anticipated to be released in the second half of 2021, according to MacroGenics, Inc.