Background and aims: The intramuscular use of beta interferon has been tested in the treatment of chronic hepatitis C, but it did not prove effective when the schedule was 3 million units three times a week for six months. Since the lack of effectiveness of this treatment might be due to the low bioavailability of beta interferon when administered intramuscularly, we tested a higher dosage of the drug: 6 million units three times a week for twelve months.
Patients and methods: Ninety-two patients were randomized to receive, intramuscularly, either 3 or 6 million units of natural human fibroblast beta interferon three times a week for 12 months.
Results: The short-term biochemical response was significantly more frequent in the group of patients who received the higher dosage of beta interferon: 21% vs 4.5% (p < 0.05). Nevertheless, a sustained biochemical response was obtained in only one patient (2%), who received the higher dosage of beta interferon.
Conclusions: Since the better short-term response rate was obtained with the higher dosage of beta interferon, a further increase in the dosage might improve the short-term and, possibly, the long-term response to treatment. However, due to the high cost of beta interferon, this high-dose schedule would probably not be cost-effective in the treatment of chronic hepatitis C.