Thymosin for the Treatment of Chronic Hepatitis B

雪绒花

By Mack Mitchell, MD

A Meta-Analysis

Meta analysis is a statistical method for comparing and combining results of different randomized trials. Most of the previous studies of thymosin for treatment of chronic hepatitis B have not shown significant improvement.

This meta-analysis reviewed the results of 5 previously published studies including a total of 435 patients. In 4/5 trials, thymosin was given for 6 months and in the other for 12 months.

Although there was no difference in the virological or biochemical response between the thymosin-treated group and the control group at the end of treatment, 6 months after treatment, the virological response was significantly greater. The biochemical response, however, remained similar between the two groups. No serious adverse events were noted.

Even though this meta-analysis suggests that there might be some benefit to thymosin treatment, current treatment with lamivudine or interferon appears to be much better. Therefore, it would seem unlikely that thymosin would find a role in treatment except possibly as part of combination therapy.

Comparison of Interferon Monotherapy with the Combination of Thymosin and Interferon

This small study compared the use of 10 MU of interferon, three times weekly for 52 weeks with the combination of 1.6 mg of thymosin a1 twice weekly and interferon in treatment of HBeAg-negative CHB. 7/10 patients treated with interferon had an end of treatment response defined as normal ALT and negative HBV DNA, but only 4/10 had a sustained response 6 months later. By contrast, 18/21 patients treated with the combination had an ETR with a sustained response rate of 16/21 or 76%.

Although the findings in this small study suggest there may be some benefit with combination therapy, the follow-up period is too short (6 months) to know whether late relapses might occur. HBeAg-negative CHB usually responds well during the first year of therapy, but relapses are frequent in the first year or two after treatment is stopped. Longer term follow-up will be needed to assess the efficacy of this combination.

5/30/01

References
H Ly Chan and others. Thymosin-a1 for the treatment of chronic hepatitis B virus (HBV) infection: A meta-analysis. Abstract 2910. Digestive Disease Week 2001. May 20-23, 2001. Atlanta, GA.

M Saruk and others. Comparison of interferon a2B monotherapy with the combination of thymosin a1 and interferon a2B in the treatment of anti-HBe-positive chronic hepatitis B in Turkey. Abstract 1949. Digestive Disease Week 2001. May 20-23, 2001. Atlanta, GA.