Clinical

HCV persistence not tied to genotype in drug users with HIV

Last Updated: 2005-10-17 16:06:46 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Coinfection with multiple hepatitis C strains does not appear to underlie the poor response to interferon-based HCV treatment seen in injection drug users with HIV, Spanish researchers report in the October 1st issue of Clinical Infectious Diseases.

"HCV-HIV-coinfected patients respond less to HCV therapy than HCV-monoinfected individuals," lead investigator Dr. Vincent Soriano told Reuters Health. "Given that most coinfected subjects were intravenous drug users, they could have been exposed repeated times to several HCV genotypes and harbor multiple HCV genotype coinfections."

Thus, he added, "exposure to interferon plus ribavirin could clear more susceptible HCV genotypes, selecting the more interferon-resistant viruses leading to therapeutic failure."

To examine whether this were the case, Dr. Soriano and colleagues at Hospital Carlos III, Madrid examined HCV genotypes at baseline and at failure in 203 coinfected patients who failed to clear HCV following treatment with interferon-based therapies.

However, Dr. Soriano continued, "no evidence for a shift in HCV genotypes was seen, indirectly suggesting that coinfection with multiple HCV genotypes in non-active IV drug users is very uncommon." It appears that "HCV recombinant viruses are exceptionally rare. This is clearly in contrast with HIV."

The reason for the lower efficacy of HCV treatment is unknown. Nevertheless, given that both interferon and ribavirin may have immunomodulatory properties, the researchers conclude that "their activity against HCV may be somewhat limited in the setting of HIV infection."

J Infect Dis 2005;192:1245-1248.