7626 Endocrine Adverse Reactions Of Tyrosine Kinase Inhibitors In Combination With Immune Checkpoint Inhibitors: A Retrospective Analysis Using The US FDA Adverse Event Reporting System

Abstract Disclosure: W. Shao: None. D. Lu: None. K. Yang: None. Y. Gao: None. J. Zhang: None. Y. Zhang: None. Background: Tyrosine kinase inhibitor (TKI) and immune checkpoint inhibitor (ICI) have been recognized to cause multiple endocrine adverse reactions (EARs). However, the combination therapy-associated EARs is still unclear. We aimed to evaluate the clinical characteristics and prognosis of EARs induced by TKI, ICI and TKI+ICI therapy. Methods: Using the US FDA Adverse Event Reporting System, 938464 cases of all adverse events, adult patients, related to the three types of treatments from January 2001 to September 2023 were identified. A total of 22275 cases were EARs and divided into TKI (n=9181), ICI (n=11363) and TKI+ICI group (n=1731). Results: The incidence of EARs was the highest in TKI+ICI group (9.1%), followed by ICI (7.7%), and TKI group (1.2%) (P < 0.05). Among patients with EARs, the proportions of female and Asian patients were significantly greater in TKI+ICI group than in the other groups (P<0.05 for all). TKI+ICI group had a larger proportion of elderly patients compared with TKI group. The most common type of EARs in TKI+ICI group was thyroid dysfunction (TD) (67.5%), followed by glucose metabolism disorder (GMD) (14.0%). Compared with TKI group, TKI+ICI group displayed a higher risk of TD (OR 3.247, 95% CI [2.849-3.701]), pituitary dysfunction (PD) (OR 6.199, 95% CI [4.534-8.474]), and primary adrenal insufficiency (PAI) (OR 4.178, 95% CI [3.470-5.031]), while the risk of GMD was lower (OR 0.136, 95% CI [0.115-0.161]). Compared with ICI group, an increasing trend of TD (OR 2.640, 95% CI [2.328-2.995]) was found in TKI+ICI group, while a lower risk of GMD (OR 0.388, 95% CI [0.328-0.459]) and PD (OR 0.312, 95% CI [0.255-0.383]) was observed in TKI+ICI group. Hypothyroidism and diabetes mellitus were the main types of TD and GMD in all three groups. Patients with polyendocrine glands involvement accounted for the largest proportion in ICI group (11.4%), followed by TKI +ICI (7.9%), and TKI group (2.3%) (P<0.05). In TKI+ICI group, elderly patients, Asians, melanoma patients were more likely to experience multi-glandular EARs. In terms of prognosis, TKI+ICI group presented a higher risk of hospitalization compared to TKI (OR 2.201, 95% CI [1.943-2.492]) and ICI group (OR 1.282, 95%CI [1.139-1.442]). However, the mortality risk of TKI+ICI group was significantly lower (OR 0.717, 95% CI [0.588-0.874]) than TKI group, and there was no significant difference compared to ICI group. Moreover, there was no difference in mortality between patients with polyendocrine and single endocrine gland involvement. Conclusions: EARs were more common in TKI+ICI therapy. The distribution of EARs in different glands varied among combination therapy and monotherapy. Combination therapy associated EARs did not increase the risk of mortality. Key words: Tyrosine kinase inhibitors, Immune checkpoint inhibitors, Combination therapy, Endocrine adverse reactions, Prognosis Presentation: 6/3/2024