Metastatic triple-negative breast cancer is an aggressive form of breast cancer with limited treatment options. Chemotherapy has been the mainstay of treatment for triple-negative breast cancer. The approval of sacituzumab govitecan represents a new targeted therapy for patients living with this aggressive malignancy.
The efficacy of sacituzumab govitecan was based on the overall response rate. The overall response rate was 33.3% (95% confidence interval [CI] = 24.6%–43.1%), with a median duration of response of 7.7 months (95% CI = 4.9–10.8). Of the patients with a response to sacituzumab govitecan, 55.6% maintained their response for 6 or more months and 16.7% maintained their response for 12 or more months.
Two percent of patients discontinued treatment due to adverse events. There were no deaths related to treatment, and no severe cases of neuropathy or interstitial lung disease.
The prescribing information for sacituzumab govitecan includes a Boxed Warning to advise health-care professionals and patients about the risk of severe neutropenia and severe diarrhea.
Continued approval of sacituzumab govitecan may be contingent upon verification of clinical benefit in the confirmatory phase III ASCENT study, which was recently halted by the independent data safety monitoring committee for compelling evidence of efficacy across multiple endpoints.