The US Food and Drug Administration (FDA) has approved Merck & Co’s Keytruda plus Roche’s Herceptin and chemotherapy in the first-line setting for HER2-positive advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma.
The approval is based on data from the ongoing phase 3 KEYNOTE-811 trial, evaluating the Keytruda (pembrolizumab), Herceptin (trastuzumab) and chemotherapy combination in patients with HER2-positive advanced gastric or GEJ adenocarcinoma who had not previously received systemic therapy for metastatic disease.
In this trial, the Keytruda/Herceptin treatment regimen plus either 5-fluorouracil plus cisplatin or capecitabine plus oxaliplatin demonstrated a statistically significant objective response rate (ORR) of 74%, compared with 52% for those who received Herceptin plus chemotherapy alone.
For patients in the Keytruda treatment group, the complete response (CR) rate was 11% and the partial response (PR) rate was 63%, while patients receiving Herceptin and chemotherapy alone achieved a CR rate of 3.1% and a PR rate of 49%.
“[This] approval marks an important milestone, as this is the first time an anti-PD-1 therapy has been approved in combination with anti-HER2 therapy and chemotherapy as a first-line treatment for these patients,” said Roy Baynes, senior vice president and head of global clinical development, chief medical officer, Merck Research Laboratories.
“From the start of Keytruda’s development, we have thoughtfully pursued novel combinations to help more patients with cancer. We are pleased to bring a new first-line combination regimen with Keytruda that has shown meaningful improvement in ORR over standard treatment to patients with HER2-positive gastric and GEJ cancer,” he added.