Abstract IA18: Early but promising data: PD-1 inhibitors in non-small cell lung cancer.

Abstract

Abstract Blockade of the programmed death (PD-1) checkpoint has emerged as a promising approach for immunotherapies in the treatment of non-small cell lung cancer (NSCLC). Immune checkpoints, such as PD-1, an inhibitory T-cell immunoreceptor, and the receptor's ligands, PD-L1 and PD-L2, assist in hindering autoimmunity and protecting peripheral tissues to minimize damage (1). However, in cancers, the interaction between PD-1 and its ligands also can result in the promotion of an immunosuppressive tumor microenvironment (1). Several agents targeting PD-1 are currently undergoing clinical development. Clinical trials of anti-PD-1 antibodies nivolumab (BMS-936558) and MK-3475 have produced encouraging results in non-small cell lung cancer patients with regards to objective response rates (ORR) and progression free survival (PFS) (2,3). In a pretreated advanced NSCLC population, nivolumab produced durable responses, particularly at 3 and 10 mg/kg doses (2). For 38 previously-treated NSCLC patients, MK-3475, administered at 10 mg/kg every three weeks, led to an ORR of 24 percent based on irRC (21 percent based on RECIST 1.1) (3). Median overall survival was 51 weeks with a PFS, which had not been reached at a time when the minimum PFS would be 62 weeks among the responders (3). ORR was 67% in patients with tumors having PD-L1 expression above a cutpoint versus 4% in those below the cutpoint (3). Based on the favorable response rates relative to historical controls, and the durability of responses in clinical trials, the development of PD-1 inhibitors in lung cancer is proceeding rapidly. Future trials utilizing anti PD-1 antibodies will explore further biomarkers, and combination with other therapies. Citation Format: Edward B. Garon, Brian R. Wolf, Deborah JL Wong, Jonathan W. Goldman. Early but promising data: PD-1 inhibitors in non-small cell lung cancer. [abstract]. In: Proceedings of the AACR-IASLC Joint Conference on Molecular Origins of Lung Cancer; 2014 Jan 6-9; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2014;20(2Suppl):Abstract nr IA18.