Genotype does not affect pattern of HCV RNA decrease among responders during interferon treatment of chronic hepatitis C

We assessed differences in the pattern of HCV RNA decrease for HCV genotype s 1, 2, and 3 during interferon treatment to determine if the lower respons e rates observed among genotype 1 patients were related to a slower decreas e in HCV clearance. Serum HCV RNA values of 472 chronic hepatitis C patient s treated with either consensus interferon (CIFN) or interferon alfa-ab (IF N alfa-2b) were evaluated. Neither virological sustained responders nor rel apsers differed in the pattern of serum HCV RNA decrease based on genotype. Virological sustained responders infected with genotype 1 cleared HCV RNA as rapidly as sustained responders who were infected with genotype 2 or 3. Relapsers had a slower rate of serum HCV RNA decrease than did virological sustained responders. Nonresponders differed in the pattern of serum HCV RN A decrease based on genotype: HCV genotype 3 patients had the greatest decr ease in serum HCV RNA; genotype 2 patients had an intermediate decrease; an d genotype 1 patients had the least serum HCV RNA decrease. HCV genotype 1 patients treated with CIFN had a greater decrease in serum HCV RNA during t herapy than did patients treated with IFN alfa-2b. However, there was no di fference in the magnitude of serum HCV RNA decrease between the two interfe ron treatments for patients infected with genotype 2 or 3. In summary, both genotype and ultimate response to treatment are determinants of the patter n and rate of serum HCV RNA change during interferon therapy of chronic hep atitis C.