Immune-related pneumonitis associated with immune checkpoint inhibitors in lung cancer: a network meta-analysis

Immune checkpoint inhibitors (ICIs) have dramatically revolutionized lung cancer treatment, providing unprecedented clinical benefits. However, immune-related pneumonitis (IRP) caused by ICIs has aroused widespread concern due to its high rate of discontinuation and mortality. This network meta-analysis (NMA) aims to compare the risks of IRP among different regimens for advanced lung cancer.

Phase II and III randomized clinical trials (RCTs) were searched from electronic databases. The rates of grade 1-5 IRP and grade 3-5 IRP were systematically extracted. An NMA was conducted among chemotherapy, ICIs monotherapy, dual ICIs combination, and ICIs+chemotherapy. Subgroup analysis was also compared based on specific types of ICIs.

Twenty-five RCTs involving 17,310 patients were eligible for inclusion. Compared with chemotherapy, ICI-based regimens were associated with an increased risk of grade 1-5 IRP and grade 3-5 IRP. Compared with ICIs+chemotherapy, ICIs monotherapy (grade 1-5: OR 2.14, 95% credible interval 1.12 to 4.80; grade 3-5: 3.03, 1.491 to 6.69) and dual ICIs combination (grade 1-5: 3.86, 1.69 to 9.89; grade 3-5: 5.12, 2.01 to 13.68) were associated with a higher risk of grade 1-5 IRP and grade 3-5 IRP. No significant difference was found between dual ICIs combination and ICIs monotherapy in grade 1-5 IRP (1.85, 0.91 to 3.37) or in grade 3-5 IRP (1.65, 0.81 to 3.37). Besides, compared with programmed cell death protein 1 (PD-1) inhibitors (2.56, 1.12 to 6.60), a lower risk of grade 1-5 IRP was observed in programmed cell death ligand 1 (PD-L1) inhibitors.

Compared with chemotherapy, using ICIs is associated with an increased risk of IRP. ICIs+chemotherapy is associated with a lower risk of IRP compared with dual ICIs combination and ICIs monotherapy. PD-1 inhibitors are associated with a higher risk of 1-5 grade IRP compared with PD-L1 inhibitors.