Acceptance, safety, and immunogenicity of a booster dose of inactivated SARS-CoV-2 vaccine in patients with primary biliary cholangitis.

Inactivated coronavirus disease 2019 (COVID-19) vaccines showed impaired immunogenicity in some autoimmune diseases, but it remains unclear in primary biliary cholangitis (PBC). This study aimed to explore the antibody response to the inactivated COVID-19 vaccine in individuals with PBC, as well as to evaluate coverage, safety, and attitudes toward the COVID-19 vaccine among them. Two cohorts of patients with PBC were enrolled in this study. One cohort was arranged to evaluate the immunogenicity of the inactivated COVID-19 vaccine, another cohort participated in an online survey. The titers of the anti-receptor-binding domain (RBD)-specific immunoglobulin G (IgG), neutralizing antibody (NAb) toward severe acute respiratory syndrome coronavirus 2 wild-type, and NAb toward Omicron BA.4/5 subvariants were detected to assess antibody response from the vaccine. After booster vaccination for more than six months, patients with PBC had significantly lowered levels of anti-RBD-specific IgG compared to HCs, and the inhibition rates of NAb toward wild-type also declined in individuals with PBC. The detected levels of NAb toward Omicron BA.4/5 were below the positive threshold in patients with PBC and HCs. Laboratory parameters did not significantly correlate with any of the three antibodies. The online survey revealed that 24% of patients with PBC received three COVID-19 vaccines, while 63% were unimmunized. Adverse effect rates after the first, second, and third vaccine doses were 6.1%, 10.3%, and 9.5%, respectively. Unvaccinated patients with PBC were more worried about the safety of the vaccine than those who were vaccinated (P = 0.004). As a result, this study fills the immunological assessment gap in patients with PBC who received inactivated COVID-19 vaccines.