Assessment of Neurologic Safety Profile of Immune Checkpoint Inhibitors: Evaluation of Adverse Drug Reaction Reports

Abstract

Background:: Immune checkpoint inhibitors (ICIs) used in immunotherapy have revolutionized cancer management. However, ICI therapy can come with serious neurologic risks. Objective:: The objective of our study is to analyze the occurrence of neurologic events with ICIs. Methods:: We referred to EudraVigilance (EV) and VigiAccess to evaluate the frequency of individual case safety reports (ICSRs), including neurologic events with ICIs. Data was gathered for a period from the date of ICI’s marketing authorization till 30 January 2023. The computational assessment was conducted with the help of reporting odds ratio (ROR) and its 95% confidence interval (CI). Results:: Overall, 8181 ICSRs in EV and 15905 ICSRs from VigiAccess were retrieved for neurologic events, with at least one ICI as the suspected drug. The majority of the ICSRs were reported for nivolumab, pembrolizumab, and ipilimumab, whereas frequently reported events were neuropathy peripheral, myasthenia gravis, seizure, Guillain-Barre syndrome, paraesthesia, syncope, encephalopathy, somnolence. Under EV, 92% of ICSRs were reported as serious, 10% included fatal outcomes, and nearly 61% cited patient recovery. Atezolizumab (ROR 1.64, 95% CI 1.75- 1.52), cemiplimab (ROR 1.61, 95% CI 1.98-1.3), and nivolumab (ROR 1.38, 95% CI 1.44-1.31) had a considerable increase in the frequency of ICSR reporting. Cerebrovascular accident, posterior reversible encephalopathy syndrome, tremor, and somnolence were identified as potential signals. Conclusion:: ICIs were significantly associated with neurologic risks, which cannot be generalized. A considerable increase in ICSR reporting frequency was observed with atezolizumab, cemiplimab, and nivolumab, while avelumab, pembrolizumab, durvalumab, and cemiplimab were linked with four potential signals. These findings suggest the consideration of a revision of the neurologic safety profile of ICIs. Furthermore, the necessity for additional ad-hoc research is emphasized.