Chronic hepatitis B virus infection is endemic in Asian communities in the United States. The purpose of the current study was to compare the antiviral efficacy of interferon-α2b in a group of adult Asian patients chronically infected with hepatitis B with active replication compared to a control group of Caucasian patients treated with the same regimen. Patients with entry aminotransferase (ALT) levels greater than three times the upper limit of normal received interferon-α2b, 5 million units, subcutaneously daily for 16 weeks. Patients with pretreatment ALT levels 1.5-3 times the upper limit of normal received prednisone for a total of six weeks prior to interferon starting at 60 mg daily with reduction in dosage by 20 mg every two weeks with a two-week period between finishing prednisone and starting interferon-α2b. Eight (62%) of the 13 Asians and six (60%) of the 10 Caucasians cleared HBeAg and HBV DNA from serum (NS). By the end of one year of follow-up after therapy, four (67%) of six Caucasian responders but none of the Asian responders had cleared hepatitis B surface antigen from serum (P < 0.05). Loss of serum markers of active replication appeared less durable in the Asian responders compared to the Caucasians with reappearance of serum HBeAg in two (25%) of eight of the former but only one (17%) of the latter group. Three other Asian patients subsequently redeveloped HBeAg in serum. It is concluded that adult Asian-Americans have an identical initial response rate to antiviral therapy with interferon-α2b; however, the response may be less durable and does not usually lead to loss of HBsAg.