Backgruound: This study investigated the incidence of endocrine immune-related adverse events (irAEs) for recently developed immune checkpoint inhibitor (ICI) drugs.
Methods: We collected studies on newly developed ICI drugs using PubMed/Medline, Embase, and Cochrane Library from inception through January 31, 2023. Among ICI drugs, nivolumab, pembrolizumab, and ipilimumab were excluded from the new ICI drugs because many papers on endocrine-related side effects have already been published.
Results: A total of 44,595 patients from 177 studies were included in this analysis. The incidence of hypothyroidism was 10.1% (95% confidence interval [CI], 8.9% to 11.4%), thyrotoxicosis was 4.6% (95% CI, 3.8% to 5.7%), hypophysitis was 0.8% (95% CI, 0.5% to 1.1%), adrenal insufficiency was 0.9% (95% CI, 0.7% to 1.1%), and hyperglycemia was 2.3% (95% CI, 1.6% to 3.4%). Hypothyroidism and thyrotoxicosis occurred most frequently with programmed cell death protein-1 (PD-1) inhibitors (13.7% and 7.5%, respectively). The rate of endocrine side effects for the combination of a programmed death-ligand 1 inhibitor (durvalumab) and cytotoxic T lymphocyte-associated antigen 4 inhibitor (tremelimumab) was higher than that of monotherapy. In a meta-analysis, the combination of tremelimumab and durvalumab had a 9- to 10-fold higher risk of pituitary and adrenal-related side effects than durvalumab alone.
Conclusion: Newly developed PD-1 inhibitors had a high incidence of thyroid-related irAEs, and combined treatment with durvalumab and tremelimumab increased the risk of pituitary- and adrenal-related irAEs. Based on these facts, it is necessary to predict the endocrine side effects corresponding to each ICI drug, diagnose and treat them appropriately, and try to reduce the morbidity and mortality of patients.
Keywords: Adrenal insufficiency; Hypophysitis; Immune checkpoint inhibitors; Thyroiditis.