Use of targeted next generation sequencing to characterize tumor mutational burden and efficacy of immune checkpoint inhibition in small cell lung cancer.

BACKGROUND: Clinically-available biomarkers to identify the fraction of patients with small cell lung cancer (SCLC) who respond to immune-checkpoint inhibitors (ICIs) are lacking. High nonsynonymous tumor mutational burden (TMB), as assessed by whole exome sequencing, correlates with improved clinical outcomes for patients with SCLC treated with ICIs. Whether TMB as assessed by targeted next generation sequencing (NGS) is associated with improved efficacy of ICIs in patients with SCLC is currently unknown. Here we determined whether TMB by targeted NGS is associated with efficacy of ICIs in patients with SCLC. METHODS: We collected clinicopathologic data from patients with relapsed or refractory SCLC which underwent targeted NGS with TMB assessment by the Dana-Farber Cancer Institute OncoPanel platform. The relationship between TMB and clinical outcomes after treatment with ICIs was investigated. RESULTS: Among the 52 patients treated with ICIs, we found no significant difference in the objective response rate (ORR) between patients with a TMB above the 50th percentile ("TMB high") and those with a TMB at or below the 50th percentile ("TMB low"). The median progression-free survival (mPFS) and median overall survival (mOS) were significantly longer in patients with a high TMB compared to those with a low TMB (mPFS: 3.3 versus 1.2 months, HR: 0.37 [95% CI: 0.20-0.69], P < 0.01; mOS: 10.4 versus 2.5 months, HR: 0.38 [95% CI: 0.19-0.77], P < 0.01). The one-year PFS and OS rates improved with increasing mutational load when TMB was divided into tertiles. CONCLUSIONS: These findings show that targeted NGS, a readily available clinical diagnostic test, can be used to identify patients with SCLC who are most likely to benefit from treatment with immune checkpoint inhibitors.

Safety and Efficacy of PD-1 Inhibitors Among HIV-Positive Patients With Non-Small Cell Lung Cancer.

INTRODUCTION: Despite widespread administration of programmed death receptor 1 (PD-1) pathway inhibitors among individuals with NSCLC, little is known about the safety and activity of these agents among human immunodeficiency virus (HIV) - infected patients since this population has largely been excluded from immunotherapy clinical trials. METHODS: Here, we describe seven patients with metastatic NSCLC and HIV infection who were treated with PD-1 inhibitors nivolumab (two cases) or pembrolizumab (five cases with three in the first-line setting). RESULTS: Partial responses to immune checkpoint inhibitors were observed in three of seven cases. Among four patients with a programmed death ligand-1 tumor proportion score ≥50%, three partial responses were observed. All patients received antiretroviral therapy while on anti-PD-1 treatment. None of the patients experienced grade 3 or 4 immune-related adverse events or immune reconstitution inflammatory syndrome, and none required PD-1 inhibitor dose interruption or discontinuation due to toxicity. CONCLUSIONS: Nivolumab and pembrolizumab can be safe and effective among patients with NSCLC and HIV. Larger studies will be needed to determine the overall safety and efficacy of immune checkpoint inhibitors among cancer patients with HIV.