Merck has secured approval from the US Food and Drug Administration (FDA) for its Keytruda plus chemotherapy to treat patients with locally recurrent unresectable or metastatic triple-negative breast cancer (TNBC) whose tumours express PD-L1 (combined positive score [CPS] ≥10) as determined by an FDA-approved test.
Keytruda (pembrolizumab), an anti-PD-1 therapy, works by enhancing the ability of the body’s immune system to identify and fight tumour cells. It is a humanised monoclonal antibody that restricts the interaction between PD-1 and its ligands, PD-L1 and PD-L2.
The approval was based on data from the phase 3 KEYNOTE-355 trial, where Keytruda in combination with chemotherapy – paclitaxel (pac), paclitaxel protein-bound (nab-paclitaxel) gemcitabine, gemcitabine (gem) and carboplatin (carbo), significantly minimised the risk of disease progression or death by 35% for patients whose tumours express PD-L1 versus the same chemotherapy regimens alone.
KEYNOTE-355 is a multicentre, double-blind, randomised and placebo-controlled trial, which evaluated 847 patients with locally recurrent unresectable or metastatic TNBC, regardless of tumour PD-L1 expression, who had not been previously treated with chemotherapy in the metastatic setting.
Merck randomised patients in 2:1 ratio to secure either Keytruda or placebo in combination with pac, nab-paclitaxel and gem/carbo.
Merck Research Laboratories global clinical development head, chief medical officer and senior vice president Dr Roy Baynes said: “Today’s approval is a significant milestone, as it represents the first approval for Keytruda in the breast cancer setting.
“In the study supporting this approval, Keytruda in combination with paclitaxel, nab-paclitaxel or gemcitabine and carboplatin significantly improved progression-free survival for patients with advanced triple-negative breast cancer whose tumours express PD-L1 with CPS greater than or equal to 10 compared with the same chemotherapy regimens alone.”
In June this year, Merck secured approval from the FDA for its Recarbrio (imipenem, cilastatin, and relebactam) to treat adults with hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP/VABP).
Imipenem is a carbapenem antibacterial, while cilastatin is a renal dehydropeptidase inhibitor, and the relebactam is a beta-lactamase inhibitor.