Background: Immune checkpoint inhibitors (ICIs) have changed the treatment paradigm of advanced-stage non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). The aim of this study was to evaluate the effectiveness and tolerance of ICIs in a real-world patient population and to investigate the predictive factors associated with survival outcomes. Methods: Medical records of patients with advanced lung cancer who started ICI monotherapy were reviewed for data collection. Treatment outcomes included objective response rate, progression-free survival (PFS), and overall survival (OS). Immune-related adverse events (irAEs) were assessed. Multiple Cox regression models were fit to investigate the predictive factors for survival outcomes. Results: We included 220 patients (median 66.5 years). Seventy-nine (35.9%) patients had Eastern Cooperative Oncology Group (ECOG) performance-status (PS) score ⩾2. Median follow-up was 11.4 months. In NSCLC, median PFS was 3.8 months (4.7 months for first line and 3.7 months for subsequent line). Median OS was 12.4 months (15.6 months for first line therapy and 11.5 months for subsequent line). In SCLC, median PFS was 1.8 months, and median OS was 4.6 months. A quarter of patients developed irAEs. There was 1 disease flare among 17 patients with pre-existing autoimmune diseases. ECOG PS of 0 to 1 and body mass index (BMI) ⩾ 25 kg/m2 (but not occurrence of irAE) were independently associated with improved OS in NSCLC, with a hazard ratio of 0.41 (95% confidence interval [CI], 0.29-0.59) and 0.62 (95% CI, 0.44-0.87), respectively. Conclusions: The clinical benefit of ICIs appears to persist in a real-world population of relatively older age, including those with poor PS and pre-existing autoimmune diseases. ECOG PS of 0 to 1 and BMI ⩾ 25 kg/m2 were independently associated with improved OS.

e20600 Background: Immune checkpoint inhibitors (ICIs) have changed the treatment paradigm of advanced NSCLC and SCLC. The populations in clinical trials generally were composed of patients (pts) with excellent performance status (PS), a minimal number of prior lines of therapy, and no history of (h/o) autoimmune disease (AD). The aim of this retrospective study was to investigate the predictors of survival in less fit and more heavily pretreated lung cancer pts at our institution. Methods: Medical records of lung cancer pts who started single-agent ICI from 2015 to 2018 were reviewed for data collection. Progression-free survival (PFS) and overall survival (OS) were compared by age, PS, smoking, PD-L1 expression, brain metastasis, prior lines of systemic therapy, h/o AD, and immune-related adverse events (irAE). Results: We included 150 pts who received at least 1 dose of nivolumab, pembrolizumab, or atezolizumab (median age 66, range 36-92, 56% female, 89% NSCLC, 97% stage 4, 13% never smoker, 34% ECOG ≥ 2, 37% ≥ 2 prior lines of therapy, 29% developed irAE). The overall response rate was 30% and clinical benefit rate 51% (3% CR, 27% PR, 21% SD). The median PFS was 3.7 months (m) overall and 12.3 m for those with ≥ 4 cycles of therapy. The median OS was 12.4 m overall and 26.0 m for those with ≥ 4 cycles. The median PFS and OS were not significantly different by age, PS, smoking, PD-L1, brain metastasis, prior lines of therapy, or h/o AD. The median OS was longer for pts with ECOG 0-1 than those ≥ 2 (14.6 vs 7.5 m, p < .001). The median PFS and OS for pts with irAE were longer compared to those without irAE (12.3 vs 2.6 m, p < .001 for PFS and 28.9 vs 9.1 m, p = .001 for OS). Multiple Cox regression analysis identified ECOG 0-1 (HR 0.54, p = .007) and irAE (HR 0.48, p = .003) to be independently associated with improved OS. 27 pts (18%) required steroids for irAE. There were no treatment-related deaths. Of 11 pts with h/o AD, only 1 experienced disease flare. Conclusions: The clinical benefit of ICIs persists in older or heavily pretreated pts. ECOG 0-1 and incident irAE predicted for improved survival. Survival for pts with ECOG ≥ 2 is very limited, suggesting ICIs should be used judiciously in this group. Therapy was well tolerated, with a low risk for flare of previous autoimmune disease.