Efficacy of PD-1/L1 inhibitors in brain metastases of non-small-cell lung cancer: pooled analysis from seven randomized controlled trials

Background: The efficacy of PD-1 or PD-L1 inhibitors in patients with brain metastases of non-small-cell lung cancer (BM-NSCLC) is inconclusive. Materials & methods: An electronic search was performed. Randomized controlled trials RCTs that compared the efficacy of PD-1- or PD-L1-inhibitor-based regimens with non-PD-1/L1 inhibitor regimens in patients with NSCLC and reported the data of subgroup patients with brain metastases were eligible for inclusion. The hazard ratios (HRs) for progression-free survival and overall survival were pooled in BM-NSCLC. Results: Seven RCTs with 472 BM-NSCLC cases are included. The pooled HRs indicated that PD-1 or PD-L1 inhibitor-based regimens reduced risk of disease progression by 44% and reduced risk of death of BM-NSCLC patients by 29% compared with non-PD-1/L1 inhibitor regimens. Conclusion: This meta-analysis indicates that PD-1 or PD-L1 inhibitors can reduce risk of both disease progression and death of patients with brain metastases of NSCLC, who have been pretreated with local therapies and/or are asymptomatic for the brain lesions.Lay abstracts The efficacy of PD-1 or PD-L1 inhibitors in patients with brain metastases of non-small-cell lung cancer (BM-NSCLC) is still inconclusive. We searched the electronic database of PubMed, Web of Science and Embase. All randomized controlled trials (RCTs) that compared the effectiveness of PD-1- or PD-L1-inhibitor-based treatment with non-PD-1/L1 inhibitor-based regimens in patients with NSCLC and reported the data of subgroup patients with brain metastases were eligible for inclusion. Finally, seven RCTs with 472 BM-NSCLC cases are included. All of these patients have been pretreated with local therapies and/or are asymptomatic for the brain lesions before joining the clinical trials. The pooled data of all trials indicated that PD-1- or PD-L1-inhibitor-based treatments reduced risk of disease progression of BM-NSCLC patients by 44% compared with non-PD-1/L1 inhibitor-based treatments. The results also showed that PD-1- or PD-L1-inhibitor-based treatments reduced risk of death of BM-NSCLC patients by 29% compared with non-PD-1/L1-inhibitor-based treatments. Our meta-analysis indicated that PD-1 or PD-L1 inhibitors can reduce risk of both disease progression and death in patients with brain metastases of NSCLC who have been pretreated with local therapies and/or are asymptomatic for the brain lesions.