Effect of metabolic dysfunction-associated steatotic liver disease on BNT162b2 immunogenicity against the severe acute respiratory syndrome coronavirus 2 omicron variant

Background and Aim: We aimed to investigate the effect of metabolic dysfunction-associated steatotic liver disease (MASLD) on three-dose BNT162b2 immunogenicity to the omicron variant. Methods: Adult recipients of three doses of BNT162b2 were prospectively recruited between May and December 2021. The serology of the neutralizing antibody by live virus microneutralization (vMN) to the omicron variant was measured at baseline, day 180, and day 360 after the first dose. The primary outcome was seroconversion (vMN titer ≥ 10) at day 360. Exposure of interest was MASLD, defined as hepatic steatosis (controlled attenuation parameter ≥ 248 dB/m on transient elastography) plus at least one of five cardiometabolic risk factors. Subjects with prior COVID-19 were excluded. A multivariable logistic regression model was used to derive the adjusted odds ratio of seroconversion with MASLD by adjusting for age, sex, antibiotic use, and proton pump inhibitor use. Results: One hundred forty-eight BNT162b2 recipients (male: 48 [32.4%]; median age: 51.0 years [interquartile range, IQR: 44.5–57.3]) were recruited. The median time from the first dose to the third dose was 8.5 months (IQR: 7.9–8.9). MASLD subjects had a lower seroconversion rate than non-MASLD ones (89.6% vs 99.0%; P = 0.007). MASLD was the only independent risk factor for seroconversion (adjusted odds ratio: 0.051, 95% confidence interval: 0.002–0.440). Subgroup analysis of immunogenicity at 4 months after the third dose shows significantly lower vMN titer (13.06 [IQR: 7.69–22.20] vs 33.49 [IQR: 24.05–46.53]; P = 0.004) and seroconversion rate (76.9% vs 97.4%; P = 0.016) in MASLD than non-MASLD subjects, but not within 4 months from the third dose (vMN titer: 46.87 [IQR: 33.12–66.02] vs 41.86 [IQR: 34.47–50.91], P = 0.240; seroconversion rate: 94.3% vs 100%, P = 0.131). Conclusion: Metabolic dysfunction-associated steatotic liver disease was a risk factor for poorer immunogenicity to the omicron variant, with a more pronounced waning effect compared among three-dose BNT162b2 recipients.