Real-world safety experience with immune checkpoint inhibitors in Saudi Arabia
Authors: Al Nuhait Mohammed , Bajnaid Eshtyag , Al Otaibi Abdulmalik , Al Shammari Abdullah , Al Awlah Yousef 
Published: March 2021

Lay abstract Real-world safety experience with immune checkpoint inhibitors in Saudi Arabia: Immune Checkpoint Inhibitors (ICIs) are rapidly growing and changing cancer care. With introduction of ICIs the landscape for cancer treatment has changed significantly. ICIs are known to induce immune-related adverse effects. This research is intended to shed light on ICIs and describe our safety experience with these agents. This study is a retrospective cohort study aimed to determine the safety of ICIs and its related adverse events at a tertiary hospital in Saudi Arabia. The study was conducted in the oncology center at King Abdulaziz Medical City, Riyadh. We identified study participants by using electronic health care system (BestCare)® to involve patients who received ICIs treatment during the study period from January 2016 up to December 2018, to include a total of 53 patients. Most of our patients were on nivolumab (37 patients) followed by atezolizumab (10 patients), and pembrolizumab (6 patients). The average number of emergency room visits after receiving treatment was three visits per patient. Renal adverse events occurred following ICIs use in nine patients, and none of the reported cases experienced a grade ≥3 event. Moreover, 13 patients experienced a hepatic adverse event, of whom only 1 patient experienced a grade ≥3 event leading to treatment discontinuation. As for diarrhea, among all patients who received ICIs, 14 patients experienced diarrhea, and 5 of them had grade ≥3 events. Also, thyroxine abnormalities occurred in seven patients. While, Pneumonitis occurred in four patients following ICIs use. In addition, we noticed other adverse events with ICIs including (skin reaction, nausea, vomiting, thrombocytopenia, neutropenia, and neurological adverse events). Furthermore, 17 patients required steroids to manage ICIs adverse events. And, no patients in our study required additional management with other immunosuppressive agents. Immunotherapies are rapidly growing and changing cancer care. Immune Checkpoint Inhibitors (ICIs) have the ability to block inhibitory checkpoints and restore the functions of the immune system. ICIs are used for the treatment of several types of cancer, and nowadays, many studies are ongoing in order to get approvals for newer indications. ICIs are known to induce immune-related adverse effects. The safety of ICIs and the most common immune-related adverse events are not yet well recognized for our population since this class of medications is lately introduced in our region, where only limited studies in our population are available in the literature. This research is intended to shed light on ICIs and describe our safety experience with these agents. This study is a retrospective cohort study aimed to determine the safety of ICIs and its related adverse events at a tertiary hospital in Saudi Arabia. The study was conducted in the oncology center at King Abdulaziz Medical City, Riyadh. Study participants were identified by using the electronic health care system (BestCare)® to include patients who were treated with ICIs during the study period from January 2016 up to December 2018. A total of 53 patients were included. Most of our patients were on nivolumab (37 patients) followed by atezolizumab (10 patients), and pembrolizumab (6 patients). The average number of emergency room visits after receiving ICIs was three visits per patient. Renal adverse events occurred following ICIs use in nine patients, and none of the reported cases experienced a grade ≥3 event. Moreover, 13 patients experienced a hepatic adverse event, of whom only 1 patient experienced a grade ≥3 event leading to treatment discontinuation. As for diarrhea, among all patients who received ICIs, 14 patients experienced diarrhea, and 5 of them had grade ≥3 events. Also, thyroxine abnormalities occurred in seven patients. While, pneumonitis occurred in four patients following ICIs use. In addition, we noticed other adverse events with ICIs, including (skin reaction, nausea, vomiting, thrombocytopenia, neutropenia, and neurological adverse events). Furthermore, 17 patients required steroids to manage ICIs adverse events. And, no patients in our study required additional management with other immunosuppressive agents. Patients treated with immune checkpoint inhibitors could have a variety of adverse drug events that might lead to treatment discontinuation and increase overall emergency room visits. This study highlights the most common adverse drug events associated with ICIs use at a tertiary care center in Saudi Arabia.