Twenty-one adult patients with chronic hepatitis B and active viral replication as indicated by the presence of hepatitis Be antigen (HBeAg), increased DNA polymerase (DNAp) and positive hepatitis B virus DNA (HBV-DNA) for more than 6 months, were entered into a prospective trial of recombinant human interferon therapy. Ten patients had chronic persistent or chronic lobular hepatitis, 8 chronic active hepatitis and 3 postnecrotic cirrhosis. All cases were treated with 5 x 10(6) units of recombinant interferon alfa-2B given subcutaneously every other day for 12 weeks. During treatment, 18 patients (86%) showed a significant reduction of DNAp levels, which reached normal values in 10 patients (48%). Viral replication was controlled over a 10-month follow-up period in 7 out of 21 patients (33%). Of these 7, five patients became HBeAg negative and HBeAb positive. HBsAg disappeared in one patient. The only serious adverse effect was thrombocytopenia in one patient in whom rapid recovery occurred when interferon was withdrawn. Treatment was also terminated in a second patient because of local reactions at the injection sites occurring after 10 weeks of therapy. Our data indicate that relatively small doses of recombinant alfa-2B interferon given during a 12-week period induce a significant reduction in viral replication and might approximately triple the spontaneous seroconversion rate observed in patients with chronic hepatitis B
