Long-term antibody response after the third dose of inactivated SARS-CoV-2 vaccine in MASLD patients.

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) patients are at an elevated risk of developing severe coronavirus disease 2019 (COVID-19). The objective of this study was to assess antibody responses and safety profiles six months after the third dose of the inactivated acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine in MASLD patients.

Methods: This study included MASLD patients and healthy volunteers without a history of SARS-CoV-2 infection. Blood samples were collected six months after receiving the third dose of the inactivated vaccine to measure the levels of neutralizing antibodies (NAbs) and anti-spike IgG antibodies against SARS-CoV-2.

Results: A total of 335 participants (214 MASLD patients and 121 healthy volunteers) were enrolled. The seroprevalence of NAb was 61.7% (132 of 214) in MASLD patients and 74.4% (90 of 121) in healthy volunteers, which was a significant difference (p = 0.018). Statistically significant differences in IgG seroprevalence were also observed between MASLD patients and healthy volunteers (p = 0.004). Multivariate analysis demonstrated that the severity of MASLD (OR, 2.97; 95% CI, 1.32-6.68; p = 0.009) and age (OR, 1.03; 95% CI, 1.01-1.06; p = 0.004) were independent risk factors for NAb negativity in MASLD patients. Moderate/severe MASLD patients had a lower NAb seroprevalence than mild MASLD patients (45.0% vs. 65.5%, p = 0.016).

Conclusion: Lower antibody responses were observed in MASLD patients six months after their third dose of the inactivated vaccine than in healthy volunteers, providing further assistance in monitoring patients who are more vulnerable to hypo-responsiveness to SARS-CoV-2 vaccines.