Hepatitis C viral kinetics during treatment with peg IFN-alpha-2b in HIV/HCV coinfected patients as a function of baseline CD4+ T-cell counts.

Background: HIV/hepatitis C virus (HCV) coinfected patients are known to have lower sustained viral response (SVR) rates than HCV monoinfected patients. However, the role of CD4+ T-cell counts on viral kinetics and outcome is not fully understood.

Methods: HCV RNA kinetics (bDNA v3, lower limit of detection [LD] = 615 IU/mL) was analyzed in 32 HIV/HCV coinfected persons treated with Pegylated-interferon-alpha2b (1.5 microg/kg weekly) and ribavirin (1-1.2 g daily) for 48 weeks and compared with results obtained from 12 HCV monoinfected patients treated with the same regimen.

Results: Baseline CD4+ T-cell counts > or =450 cells/mm3 were significantly (P < 0.002) associated with SVR in coinfected genotype 1 patients. First phase decline was significantly lower among patients with low as compared with high CD4 counts (P < 0.03) and among coinfected compared with monoinfected patients (P < 0.002). Second phase decline slope showed a similar trend for coinfected patients.

Conclusions: Low baseline CD4+ T-cell count is associated with slower HCV viral kinetics and worse response to treatment among HIV coinfected patients, suggesting HCV treatment response depends on immune status. HCV genotype 1 coinfected patients have slower first phase viral kinetics than HCV monoinfected patients. First phase viral decline (>1.0 log) and second phase viral decline slope (>0.3 log/wk) are excellent predictors of SVR for coinfected patients.