In a small, uncontrolled study of 20 people with chronic hepatitis B, giving thymosin‑alpha‑1 injections (1.6 mg under the skin twice a week for six months) lowered liver enzymes and led to a sustained virologic response in about a quarter of participants, but it didn’t clear the virus completely and no major side effects were seen.

Interferon treatment for chronic hepatitis B has low efficacy and is associated with serious side effects. It is therefore important to assess the role of other drugs in the treatment of this condition. To assess the efficacy and safety of thymosin alpha in 20 patients with hepatitis B-related liver disease. Patients with chronic hepatitis B, HBV DNA positivity, ALT more than 1.5 times the upper limit of normal and liver biopsy showing chronic hepatitis or cirrhosis were treated with thymosin alpha 1.6 mg subcutaneously twice a week for 6 months. Biochemical and serological markers were assessed pre-treatment, immediately post treatment, and 6 months and 1 year after end of treatment. Of 20 patients, 15 had chronic hepatitis and 5 had cirrhosis on histology; 17 were HBeAg-positive and 3 were HBeAg-negative. Eight patients were interferon non-responders and 12 were naïve patients. Four patients had end-of-treatment response and two additional patients had a delayed response within 6 months of treatment; one responder had a relapse within 1 year of treatment. Overall sustained response rate was 25% (5 of 20). No patient cleared HBsAg. Reduction in ALT levels was observed after treatment and persisted one year later. No significant side effects were observed. Thymosin alpha is a safe and effective alternative treatment modality in chronic hepatitis B.