THU0630 Immune-related adverse events associated with immune checkpoint inhibitors in spanish patients

Background Immune checkpoint inhibitors (ICI), a type of immunotherapy which block negative co-stimulation of T-cells, have surfaced as an important alternative of treatment for advanced malignancies. Unfortunately, these agents have been associated with immune-related adverse events (irAE). Objectives To analyse the frequency, type and outcome of irAE in Spanish patients treated with ICI. Methods We carried out a retrospective, observational and longitudinal study, including adult patients diagnosed with cancer and treated with ICI followed in our centre (Spanish university hospital) from October 2012 to December 2017. Demographics, clinical, therapeutic and outcome date were collected from their medical records. Results We included 125 patients, 66.4% males, all them Caucasians, with a mean age at diagnosis 63 years (range:42–81). The most common types of cancers were lung carcinoma (61.6%) and melanoma (12.8%). The ICI most frequently used was nivolumab (29.6%), followed by pembrolizumab (8.8%) and atezolizumab (8.8%), as monotherapy. It was also common, combinations, or the use of consecutive way with different drugs. Occurrence of irAE was reported in 51 patients (table 1) and the systems more frequently involved were gastrointestinal tract, endocrine glands and skin. Most of these cases were treated steroids at high doses but a case of colitis required infliximab. Withdrawal of immunotherapy was required in almost half of the adverse events (45%). During the follow-up period there were 5 deaths associated with irAE. Conclusions The frequency and type of irAE associated ICI in our series were similar to those reported in previous studies, except for rheumatological events, being arthritis and sicca syndrome the most frequently reported in other series. These adverse events are not rare and may be a potential cause of morbity in these patients, so it is important to recognise them early and treat properly, with the rheumatologist being one of the specialists involved. Disclosure of Interest None declared