Keytruda plus chemotherapy results in statistically significant improvement in PFS compared to chemotherapy alone

NJ- Merck has announced that the Phase 3 KEYNOTE-604 trial investigating KEYTRUDA, Merck’s anti-PD-1 therapy, in combination with chemotherapy met one of its dual primary endpoints of progression-free survival (PFS) in the first-line treatment of patients with extensive-stage small-cell lung cancer (ES-SCLC).

In the study, treatment with KEYTRUDA in combination with chemotherapy (etoposide plus cisplatin or carboplatin) resulted in a statistically significant improvement in PFS compared to chemotherapy alone (HR=0.75 [95% CI, 0.61-0.91]), which was observed at a prior interim analysis. At the final analysis of the study, there was also an improvement in overall survival (OS) for patients treated with KEYTRUDA in combination with chemotherapy compared to chemotherapy alone; however, these OS results did not meet statistical significance per the pre-specified statistical plan. The safety profile of KEYTRUDA in this trial was consistent with that observed in previously reported studies. Results will be presented at an upcoming medical meeting and discussed with regulatory authorities.

“Results of KEYNOTE-604 demonstrated the potential of KEYTRUDA, in combination with chemotherapy, to improve outcomes for patients newly diagnosed with extensive-stage small cell lung cancer, a highly aggressive malignancy,” said Dr. Roy Baynes, senior vice president and head of global clinical development, chief medical officer, Merck Research Laboratories. “We sincerely thank the patients and investigators for their participation in this study and are committed to helping patients who face difficult-to-treat types of lung cancer.”

In addition to KEYTRUDA’s five current indications in lung cancer, Merck is continuing to study KEYTRUDA across multiple settings and stages of lung cancer through a broad clinical program, which is comprised of more than 10,000 patients enrolled or expected to be enrolled across 20 Merck-sponsored clinical studies.

KEYNOTE-604 is a randomized, double-blind, placebo-controlled Phase 3 trial (ClinicalTrials.gov, NCT03066778) investigating KEYTRUDA in combination with chemotherapy compared to chemotherapy alone in patients with newly diagnosed ES-SCLC. The dual primary endpoints were OS and PFS. Secondary endpoints included objective response rate (ORR), duration of response (DOR), safety and quality of life (QoL).

Lung cancer, which forms in the tissues of the lungs, usually within cells lining the air passages, is the leading cause of cancer death worldwide. Each year, more people die of lung cancer than die of colon and breast cancers combined. The two main types of lung cancer are non-small cell and small cell. Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for about 85% of all cases. Small cell lung cancer (SCLC) accounts for about 10 to 15% of all lung cancers. The five-year survival rate for patients diagnosed in the U.S. with any stage of SCLC is estimated to be 6%.