Merck gets European Commission nod for two new indications for Keytruda in gastrointestinal cancers

• KEYTRUDA in combination with fluoropyrimidine- and platinum-containing chemotherapy, for the first-line treatment of locally advanced unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric or gastroesophageal junction (GEJ) adenocarcinoma in adults whose tumors express PD-L1 with a Combined Positive Score (CPS) ≥1;
• KEYTRUDA in combination with gemcitabine and cisplatin for the first-line treatment of locally advanced unresectable or metastatic biliary tract carcinoma (BTC) in adults.

These approvals by the EC follow positive recommendations from the Committee for Medicinal Products for Human Use received in October 2023 and November 2023 and were based on overall survival (OS) results from the Phase 3 KEYNOTE-859 and KEYNOTE-966 trials, respectively.

In KEYNOTE-859, KEYTRUDA plus chemotherapy significantly improved OS in the overall patient population, reducing the risk of death by 22% (HR=0.78 [95% CI, 0.70-0.87]; p<0.0001) compared to chemotherapy alone at a median follow-up of 12.0 months (range, 0.1 to 45.9 months). In patients whose tumors expressed PD-L1 (CPS ≥1), KEYTRUDA plus chemotherapy reduced the risk of death by 26% (HR=0.74 [95% CI, 0.65-0.84]; p<0.0001). Median OS was 13.0 months (95% CI, 11.6-14.2) for patients treated with KEYTRUDA plus chemotherapy vs 11.4 months (95% CI, 10.5-12.0) for chemotherapy alone. In the study, approximately 80% of patients had tumors which expressed PD-L1 (CPS ≥1).

In KEYNOTE-966, KEYTRUDA plus chemotherapy demonstrated a statistically significant improvement in OS, reducing the risk of death by 17% (HR=0.83 [95% CI, 0.72-0.95]; one-sided p=0.0034) compared to chemotherapy alone at the trial’s pre-specified final analysis for OS. Median OS was 12.7 months (95% CI, 11.5-13.6) for KEYTRUDA plus chemotherapy versus 10.9 months (95% CI, 9.9-11.6) for chemotherapy alone.

“KEYTRUDA has shown its potential as an important treatment option in the EU across a number of gastrointestinal cancers, with seven indications based on data from our extensive clinical development program,” said Dr. Marjorie Green, senior vice president and head of late-stage oncology, global clinical development, Merck Research Laboratories. “With these two new approvals of KEYTRUDA-based regimens in advanced HER2-negative gastric and gastroesophageal junction cancer and advanced biliary tract cancer, Merck continues to demonstrate progress in providing treatment options to patients in Europe.”

The safety of KEYTRUDA plus chemotherapy has been evaluated in 4,787 patients across tumor types. In KEYNOTE-859, the incidence of Grade 3-5 adverse reactions in patients with gastric cancer was 75% for KEYTRUDA plus chemotherapy and 70% for chemotherapy. In KEYNOTE-966, the incidence of Grade 3-5 adverse reactions in patients with BTC was 85% for KEYTRUDA plus chemotherapy and 84% for chemotherapy alone.

These approvals allow marketing of these KEYTRUDA regimens for these indications in all 27 EU member states, as well as Iceland, Liechtenstein, Norway and Northern Ireland. With these decisions, KEYTRUDA is now approved for 26 indications in the EU, including seven in gastrointestinal cancers.

Merck has an extensive clinical development program evaluating KEYTRUDA in gastrointestinal cancers and is continuing to study KEYTRUDA for multiple uses in gastric, hepatobiliary, esophageal and colorectal cancers.