In a small trial of 44 chronic hepatitis B patients without the protective anti‑HBe antibody, giving thymosin‑alpha‑1 for six months didn’t cure the infection or dramatically improve viral markers compared with doing nothing, but it was safe and seemed to keep liver enzymes (ALT) lower, suggesting a modest anti‑inflammatory effect.

No consistently effective therapy is yet available for the treatment of chronic HBsAg, anti-HBe, HBV-DNA-positive hepatitis. A multicenter trial has shown that the response rates are not significantly different when patients with anti-HBe-positive hepatitis are treated with six-month course of thymosin-alpha1 or of interferon-alpha. However, since among these patients, interferon's real efficacy is still debated, with sustained biochemical response achieved in only a few of the treated patients, we conducted this controlled study to investigate the safety and efficacy of thymosin-alpha1 as compared with no treatment. Forty-four chronic hepatitis B virus (HBV) carriers, who were anti-HBe- and HBV-DNA-positive, were randomized, with stratification for the presence of cirrhosis at baseline liver biopsy, to receive either thymosin-alpha1 at a dose of 900 microg/m2 twice a week for six months or no treatment. At entry, both groups of patients were comparable for sex, age, liver histology, ALT, IgM anti-HBc, and HBV-DNA levels. Forty-two patients were followed-up for 20 months (median; range 12-32 months) after completion of therapy: one dropped out, and one developed hepatocellular carcinoma at six months. Thymosin-alpha1 treatment had no side effects. Six months after the end of the therapy, HBV-DNA was negative and ALT had normalized in 14% of treated cases and in 4.5% of control group, while IgM anti-HBc was negative (<0.200) in 14% of the treated patients and in 4.5% of the controls. Among the treated patients, the median ALT levels stayed significantly lower compared to the pretreatment values during the treatment period and six months of follow-up. During the first year, there were six flares of hepatitis in the control group and five among the treated patients (P = NS), yielding a per year average of 0.3 and 0.23 flares per patient, respectively. Among the treated patients, median IgM anti-HBc levels were low with respect to baseline values 4-10 months after treatment started. None became HBsAg negative. In conclusion, these results indicate that, in anti-HBe, HBV-DNA-positive chronic hepatitis B, thymosin-alpha1 therapy alone does not increase the response rate, but may contribute to reduce the immune-mediated liver cell necrosis as indirectly assessed by ALT and IgM anti-HBc levels.