R1438

R1438 is a code name that has been used to refer to two distinct drug candidates developed by Roche: a dual PPARα/γ agonist and a monoclonal antibody targeting the insulin-like growth factor 1 receptor (IGF-1R), the latter more commonly known as RG1507. The PPAR agonist R1438 is a non-thiazolidinedione small molecule that was investigated for the treatment of type 2 diabetes mellitus and insulin resistance. It functions by simultaneously activating PPARα and PPARγ, thereby improving insulin sensitivity and optimizing lipid metabolism. This candidate was eventually discontinued in favor of its successor, aleglitazar (R1583). The second agent, RG1507 (sometimes referred to as R1438 in early Roche pipeline documents), is a fully human monoclonal antibody designed to inhibit IGF-1R signaling, which plays a critical role in tumor cell proliferation and survival. RG1507 reached Phase 2 clinical trials for various malignancies, including Ewing's sarcoma and non-small cell lung cancer (NSCLC), before its development was discontinued in 2011 as part of a strategic portfolio prioritization.