Peginterferon alfa-2a (40KD) (PEGASYS®) plus ribavirin (COPEGUS®) in retreatment of chronic hepatitis C patients, nonresponders and relapsers to previous conventional interferon plus ribavirin therapy

Peginterferon alfa plus ribavirin is currently the treatment of choice for chronic hepatitis C. Peginterferon alfa-2a (40KD) plus ribavirin has given an overall sustained virological response of 18 percent in F3/F4 previous nonresponder US patients. We evaluated the effectiveness of peginterferon alfa-2a (40KD) plus ribavirin in Brazilian patients who were relapsers or nonresponders to previous interferon-based therapy. One-hundred-thirty-four patients with biopsy-proven chronic hepatitis C, HCV RNA positive, elevated ALT and who were either relapsers (n=37) or nonresponders (n=97) to at least 24 weeks of conventional interferon/ribavirin therapy were retreated with peginterferon alfa-2a (40KD) 180mg/qw and ribavirin 800mg bid for 48 weeks. Efficacy was assessed as virological response (defined as undetectable HCV RNA) at the end of treatment (EoT) and at the end of follow-up (SVR - Sustained Virological Response). Safety assessments consisted of clinical and laboratory evaluations. In the patient sample, 72 percent were genotype 1 and 34 percent were cirrhotic. In an intention-to-treat analysis, relapser patients showed 78 percent EoT response and 51 percent SVR. Nonresponders showed 57 percent EoT response and 26 percent SVR. Positive predictive factors of SVR were non-1 genotype and relapser state. Six percent of the patients interrupted treatment because of adverse events and 45 percent had dose reduction (mainly associated with leucopenia and anemia). Brazilian patient relapsers and nonresponders to conventional interferon and ribavirin treatment can achieve a sustained virological response when retreated with peginterferon alfa-2a (40KD) and ribavirin. The safety profile is similar to that of naive patients.

Geographic distribution of hepatitis C virus genotypes in Brazil

Brazil is a country of continental dimension with a population of different ethnic backgrounds. Thus, a wide variation in the frequencies of hepatitis C virus (HCV) genotypes is expected to occur. To address this point, 1,688 sequential samples from chronic HCV patients were analyzed. HCV-RNA was amplified by the RT-PCR from blood samples collected from 1995 to 2000 at different laboratories located in different cities from all Brazilian States. Samples were collected in tubes containing a gel separator, centrifuged in the site of collection and sent by express mail in a refrigerated container to Laboratório Bioquímico Jardim Paulista, São Paulo, SP, Brazil. HCV- RNA was extracted from serum and submitted to RT and nested PCR using standard procedures. Nested PCR products were submitted to cycle sequencing reactions without prior purification. Sequences were analyzed for genotype determination and the following frequencies were found: 64.9 percent (1,095) for genotype 1, 4.6 percent (78) for genotype 2, 30.2 percent (510) for genotype 3, 0.2 percent (3) for genotype 4, and 0.1 percent (2) for genotype 5. The frequencies of HCV genotypes were statistically different among Brazilian regions (P = 0.00017). In all regions, genotype 1 was the most frequent (51.7 to 74.1 percent), reaching the highest value in the North; genotype 2 was more prevalent in the Center-West region (11.4 percent), especially in Mato Grosso State (25.8 percent), while genotype 3 was more common in the South (43.2 percent). Genotypes 4 and 5 were rarely found and only in the Southeast, in São Paulo State. The present data indicate the need for careful epidemiological surveys throughout Brazil since knowing the frequency and distribution of the genotypes would provide key information for understanding the spread of HCV.