IFNA2 and cryohydrocytosis: In 1998, two multicenter randomized controlled trials (RCTs) (one U.S. study and one international study) totaling 1,744 previously untreated patients with compensated CHC compared 24- and 48-week drug regimens of IFN-α-2b monotherapy (3 MUs 3 times weekly) with those of IFN-α-2b and ribavirin (1.000 mg/day or 1.200 mg/day for patients weighing <75 kg or >75 kg, resp).