In a phase III study, the administration of pembrolizumab with chemotherapy provided progression-free survival and overall survival benefits with a satisfactory safety profile compared to placebo in previously untreated patients with metastatic squamous non-small-cell lung cancer.
The KEYNOTE-407 phase III study assessed the long-term survival outcomes in metastatic squamous non-small-cell lung cancer (NSCLC) patients treated with pembrolizumab plus chemotherapy compared to treatment with placebo plus chemotherapy.
The current study is a 5-year follow-up of the KEYNOTE-407 trial to assess the long-term survival outcomes in these patients. The findings are published in the Journal of Clinical Oncology.
Study Participants
A total of 278 and 281 patients were enrolled in the pembrolizumab plus chemotherapy and placebo plus chemotherapy groups, respectively. Subsequent therapy was administered to 109 patients receiving pembrolizumab plus chemotherapy and 172 patients receiving placebo plus chemotherapy. Of the patients in the pembrolizumab plus chemotherapy group, 12 underwent a second course of pembrolizumab, and 55 completed 35 cycles of pembrolizumab.
Treatment Efficacy of Pembrolizumab Plus Chemotherapy
The estimated 5-year overall survival rates among patients in the pembrolizumab plus chemotherapy and placebo plus chemotherapy groups were 18.4% and 9.7%, respectively. The estimated 5-year progression-free survival rates among patients in the pembrolizumab plus chemotherapy and placebo plus chemotherapy groups were 10.8% and 3.5%, respectively. The objective response rate was 62.2% in patients receiving pembrolizumab with chemotherapy and 38.8% in patients receiving placebo with chemotherapy.
Safety Outcomes of Pembrolizumab Plus Chemotherapy
Infusion reactions and immune-mediated adverse effects occurred in approximately 35.6% of patients administered pembrolizumab with chemotherapy and 9.3% of patients administered placebo with chemotherapy.
Characteristics of Patients Completing 35 Cycles of Pembrolizumab
Among 55 patients who completed 55 cycles of pembrolizumab, nine patients had a complete response, 41 patients had a partial response, and five patients had stable disease. Following the completion of 35 treatment cycles, the 3-year overall survival rate was 69.5%. Immune-mediated adverse events and infusion reactions were observed in 21 of these patients.
Source:
Novello, S., Kowalski, D. M., Luft, A., Gümüş, M., Vicente, D., Mazières, J., Rodríguez-Cid, J. R., Tafreshi, A., Cheng, Y., Lee, K. H., Golf, A., Sugawara, S., Robinson, A., Halmos, B., Jensen, E., Schwarzenberger, P., Pietanza, M. C., & Paz-Ares, L. (2023). Pembrolizumab plus Chemotherapy in squamous Non–Small-Cell lung Cancer: 5-Year Update of the Phase III KEYNOTE-407 Study. Journal of Clinical Oncology, 41(11), 1999–2006. https://doi.org/10.1200/jco.22.01990
