Details of the KEYNOTE-189 study have been announced by Merck (known as MSD outside the United States and Canada).
The results demonstrate that its anti-PD-1 therapy, KEYTRUDA (pembrolizumab), significantly improves overall survival (OS) in combination with pemetrexed (ALIMTA®) and cisplatin or carboplatin for the first-line treatment of metastatic nonsquamous non-small cell lung cancer (NSCLC), reducing the risk of death by half compared with chemotherapy alone.
“The results of this trial have the potential to change the treatment paradigm for patients with nonsquamous NSCLC in the first-line setting, including patients whose tumors are either PD-L1 negative or are untested,” explained Roger Perlmutter, Merck Research Laboratories (NJ, USA).
Furthermore, the addition of pembrolizumab to pemetrexed plus platinum chemotherapy achieved a significant improvement in progression-free survival (PFS), with a reduction in the risk of progression or death of nearly half for patients in the pembrolizumab combination arm, compared with chemotherapy alone.
A PFS improvement in the pembrolizumab combination group was observed in patients whose tumors were negative for PD-L1; patients with a tumor proportion score of 1–49%; and patients with a tumor proportion score greater than or equal to 50%.
Pembrolizumab is the first immunotherapy to significantly extend survival of patients with nonsquamous NSCLC in combination with chemotherapy as a first-line treatment.