Combined application of bevacizumab and PD-1 blockade displays durable treatment effects by increasing the infiltration and cytotoxic function of CD8(+) T cells in lung cancer

Plain language summary Immune checkpoint inhibitors can improve long-term survival in advanced non-small-cell lung cancer, but the promising clinical benefit was only observed in a minority of patients. The combination of VEGF/VEGFR inhibitors and immune checkpoint inhibitors has become an attractive strategy. In this study, lung carcinoma mouse models were used to investigate the therapeutic efficacy of combined bevacizumab and anti-PD-1 antibody. The authors demonstrated that the combined application of bevacizumab and PD-1 blockade displays durable treatment effects by increasing the infiltration and cytotoxic function of CD8(+) T cells. This study also reports a non-small-cell lung cancer patient who benefited from this treatment regimen as fourth-line therapy. Aim: VEGF/VEGFR inhibitors may help immune checkpoint inhibitors expand the population that will benefit from treatment. The authors investigated the efficacy of combined bevacizumab and PD-1 antibody. Materials & methods: C57BL/6J mice were injected subcutaneously with 1 x 10(6) Lewis lung carcinoma cells. The mice were intraperitoneally injected with 0.25 mg anti-PD-1 inhibitors and/or 15 mg/kg bevacizumab. Tumor tissues were harvested. The authors reported that a non-small cell lung cancer patient received 200 mg PD-1 antibody combined with 7.5 mg/kg bevacizumab as fourth-line treatment. Results: Bevacizumab combined with PD-1 antibody induced a strong and durable antitumor effect. Bevacizumab combined with PD-1 antibody improved abnormal tumor vessels and enhanced the cytotoxic function and infiltration of T lymphocytes. The patient's survival time was significantly prolonged. Conclusion: Bevacizumab combined with anti-PD-1 antibody induces a durable antitumor effect by increasing the infiltration and cytotoxic function of CD8(+) T cells in lung cancer.