Reuters Health Information (2005-10-17): HCV persistence not tied to genotype in drug users with HIV
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
"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
J Infect Dis 2005;192:1245-1248.