Abstract
Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4), an immune-checkpoint receptor and regulator of T-cell activation, has become an important therapeutic target for immunotherapy in cancer and autoimmune diseases. To date, clinical trials involving cancer immunotherapies, such checkpoint blocking antibodies directed at CTLA-4 (ipilimumab), have excluded patients with underlying autoimmune disease given concern for potential triggering of autoimmune exacerbations. We present the first known cases to our knowledge of two patients with active autoimmune diseases who received ipilimumab. In this limited clinical experience, no serious exacerbations of underlying autoimmunity have yet been observed, and one patient benefited from ipilimumab. These cases advocate for further investigation of the safety of cancer immunotherapies in cancer patients with underlying autoimmune conditions in carefully designed clinical trials with cautious monitoring.