Pembrolizumab Combination Receives FDA Approval in Triple-Negative Breast Cancer
Posted: Wednesday, July 28, 2021
On July 26, the U.S. Food and Drug Administration (FDA) approved the use of the anti–PD-1 therapy pembrolizumab (Keytruda) for the treatment of patients with high-risk early-stage triple-negative breast cancer in combination with chemotherapy as neoadjuvant treatment and then continued as a single agent as adjuvant treatment after surgery. The FDA approval marks 30 indications for pembrolizumab in the United States.
Additionally, the FDA moved from accelerated approval to full approval of pembrolizumab in combination with chemotherapy for patients with locally recurrent unresectable or metastatic triple-negative breast cancer whose tumors express PD-L1, as determined by an FDA-approved test.
The multiple FDA approvals are from updated results from the multicenter phase III KEYNOTE-522 clinical trial. The study enrolled 1,174 patients with newly diagnosed previously untreated high-risk early-stage triple-negative breast cancer with a tumor size between 1 and 2 cm, with nodal involvement or tumor size greater than 2 cm regardless of nodal involvement. Patients were also enrolled regardless of PD-L1 expression. Patients were excluded from the study if they had an active autoimmune disease that required systemic therapy within 2 years of treatment or a medical condition that required immunosuppression were ineligible.
Patients who received pembrolizumab in combination with carboplatin and paclitaxel, followed by doxorubicin or epirubicin and cyclophosphamide before surgery and continued as a single agent after surgery, demonstrated a significantly longer event-free survival than did patients given the same neoadjuvant chemotherapy regimens without pembrolizumab. In addition, there was a 37% decrease in the risk of disease progression that ruled out definitive surgery, a local/distant recurrence, a second primary cancer, or death from any cause (P = .00031).