MA15.09 Response to the Treatment Immediately before Nivolumab Monotherapy May Predict Clinical Response to Nivolumab

Abstract

Nivolumab was approved in Japan on December 17, 2015 for previously treated non-small cell lung cancer (NSCLC). The expression of programmed death-ligand 1 (PD-L1) in tumor tissue is considered a predictive factor for clinical response to nivolumab. However, in Japan, there are no commercially available diagnostic kits for evaluating PD-L1 expression. In addition, little is known regarding other predictive factors of response to nivolumab monotherapy in patients with NSCLC. Therefore, we examined the relationships between the response to nivolumab monotherapy and clinical parameters in patients with NSCLC. Between December 2015 and April 2016, we performed a retrospective analysis of 50 patients with NSCLC treated with nivolumab monotherapy (3 mg/kg, every 2 weeks) at our Institution in the clinical setting. Baseline characteristics of patients who received nivolumab monotherapy were: median age, 65 years [range:39–76]; 60% male; 26% ECOG-PS 0, 64% ECOG-PS 1; 38% smoker; 58% stage IV disease, 22% postoperative recurrence; 80% non-squamous (SQ) NSCLC; 36% non-SQ NSCLC patients had active EGFR mutations; 20% second-line, 18% third-line. The objective response rate (ORR) for all patients treated with nivolumab monotherapy was 18% (95%CI 10–31). Univariate analysis revealed that predictive factors of response to nivolumab monotherapy were associated with “SQ”, “response to the treatment immediately before nivolumab monotherapy”, “therapeutic line of nivolumab (second-line and third-line treatment)” and “smoker” categories (Table 1). In the multivariate logistic regression analysis, the independent predictive factors were “SQ” (P = 0.0069) and “response to the treatment immediately before nivolumab monotherapy” (P < 0.0001) (Table 1). “Response to the treatment immediately before nivolumab monotherapy”, other than “SQ” histology may be predictors of clinical response to nivolumab in patients with NSCLC.