Efficacy and safety of immune checkpoint inhibitors in advanced solid tumors with hepatitis B infection.

12037 Background: Hepatitis B virus (HBV) infection is related to cirrhosis and hepatocellular carcinoma (HCC). The breakthroughs of immunotherapy (IO) have dramatically changed treatment paradigms in malignancies based on considerable survival benefits. Advanced tumor patients are under risk of HBV reactivation after IO, and serum HBV DNA positive (HBV+) is regarded as the exclusion of clinical study. It is urgent to explore the impact of HBV infection on the efficacy and safety of IO. Methods: A retrospective review of advanced tumors patients with HBV infection who received IO was performed at the First Affiliated Hospital of Anhui Medical University and Fuyang Cancer Hospital between January 1, 2019, and August 31, 2023. 563 patients were included, of which 346 were HCC patients. The long-term efficacy is overall survival (OS). CTCAE 5.0 was used to evaluate the hepatic adverse event. Results: In advanced tumor, patients who have had HBV+ had higher incidence of hepatic adverse events (hAE) ( P<0.001) and severe hepatic adverse events (hSAE) ( P=0.001) than HBV negative (HBV-). Among HBeAg positive(HBeAg+) hepatitis patients, there was no difference in hAE ( P=0.131) and hSAE ( P=0.431) between HBV+ and HBV- patients. However, in HBeAg negative (HBeAg-) patients, HBV+ patients have a significantly higher incidence of hAE ( P=0.003) and hSAE ( P=0.001) than HBV-. In HCC, there was no statistical difference in OS between HBV+ and HBV- patients (P=0.132), with 91.0% patients received antiviral treatment. HBV+ patients had more hAE ( P=0.023) and hSAE ( P=0.020). HBV+ HBeAg- patients had more hSAE than HBV- ( P=0.022). In HBeAg+ patients, there was no difference in OS ( P=0.755), hAE ( P=0.199) and hSAE ( P=0.426) between HBV+ and HBV-. In non-HCC, antiviral treatment brought more hAE ( P=0.025), which existed in HBeAg- ( P=0.029) and HBV- ( P=0.047). Thirty HCC patients converted HBV- to HBV+ during IO (mOS: 527d, 95% CI: 266.22-787.78), of which 2 patients had an ALT flare, of which 28 patients had hAE and 10 patients had hSAE. Conclusions: HBV+ patients have higher incidence of hAE and hSAE. In HCC, HBV+ patients are more likely to occur hAE and hSAE. HBV+ HCC patients had worse OS than who remained HBV- during ICIs. For non-HCC patients with antiviral treatment, there was no difference in OS or AEs and SAEs, regardless of infection status and HBV status. In HBeAg+ HCC patients, there was no statistical difference in OS, hAE, and hSAE regardless of HBV activity. Antiviral treatment was associated with a higher incidence of hAE and hSAE irrespective of tumor, infection status, and HBV DNA status. In advanced HCC, 18.9% of HBV- patients turned HBV+, which not only have worse OS and greater hepatic toxicity. Dynamic monitoring of HBV-related serological indicators and liver enzymes is needed for hepatitis B patientsduring IO, and HBV reactivation is a sign of poor clinical prognosis.