Hepatitis B virus genotype B is associated with better response to thymosin α1 therapy than genotype C

Hepatitis B virus (HBV) genotype has been reported to correlate with response to interferon treatment in several studies. The relationship between HBV genotype and thymosin α1 (T-α1) treatment is unknown. We retrospectively examine HBV genotypes, precore and core promoter mutations in patients treated with Tα1 and analyse the correlation between complete response [alanine aminotransferase (ALT) normalization plus seroclearance of HBeAg and HBV-DNA] and HBV genotype. It consisted 98 patients with chronic hepatitis B randomly allocating to three groups: (i) T6 group (n = 32) received a 26-week course of Tα1 1.6 mg two times a week; (ii) T12 group (n = 34) received the same regimen as T6 group, but Tα1 therapy extended for 52 weeks; (iii) T0 group (n = 32) served as a control and was followed up for 18 months without specific treatment. Stepwise logistic regression analysis showed that genotype (OR, 3.747; 95% CI, 1.066-13.170; P = 0.039), precore mutation (OR, 6.285; 95% CI, 1.874-21.086; P = 0.003) and Tα-1 treatment (OR, 12.045; 95% CI, 2.220-65.354; P = 0.004) as independent factors associated with complete response. The complete response of Tα-1 therapy was higher in patients with genotype B compared to patients with genotype C (52%vs 24%; P = 0.036) and in patients with precore mutation (64%vs 19%; P = 0.002). In conclusion, genotype, presence of precore mutation and Tα-1 therapy were independent predictors to complete response. Genotype B, compared to genotype C, is associated with a higher response rate to T-α1 therapy.