Background:    HIV/Hepatitis C Virus (HCV) co-infection leads to accelerated  rates of progression to cirrhosis. HCV may adversely influence immunological progression in HIV disease. A recent study of HIV/HCV co-infection showed impaired CD4 recovery after initiation of HAART. Our aim was to assess the efficacy of combination therapy with IFN/RBV in our HIV/HCV cohort, and to evaluate the impact of clearance of HCV on CD4 lymphocyte count.

Methods:  Treatment outcomes were analysed retrospectively in 93 patients (pts) with HIV/HCV, treated with Pegylated (PEG) or standard IFN and RBV. Patients were defined as having an sustained viral response if HCV RNA levels were undetectable 6 months post treatment. CD4 counts at 6 months post therapy were compared to baseline in a subgroup of 39 patients, 16 sustained viral responders and 23 non-responders. Change in CD4 count was analyzed using an ANOVA model.

Results:  Baseline demographic, clinical and virological data was available on 65/93 (70%) subjects. Mean age was 48.2 years, 14/65 (20%) were female. Previous opportunistic infections or CD4 nadir<200 were noted in 16/65 (25%), 57/65 (88%) were on HAART at presentation. Median CD4 count was 476 x10⁶/L (119-1612), and 48/65 (74%) had a BL HIV RNA of <400 copies/ml. Median BL HCV RNA level was 4,560,000 copies/mL (130,000 to 35,000,000), 46/65 (71%), had HCV genotype 1. Baseline liver biopsy median stage was 2 (0-4), 10/53 (19%) had stage 3 or 4. Prior therapy with IFN was noted in 16/65(25%). PEG-IFN was used in 47/65 (72%), median dose of RBV was 1000 mg (400 to 1200). G-CSF was used for neutropenia in 4/65 (6%), and 27/65 (41.5%) received rHuEPO for anemia, 3/65 (4.6%) were transfused. Outcome was definable in 79/93 (85%). Of 79, 17 (21.5%) discontinued therapy before 20 weeks; 4 patients were lost to follow-up. Using an intention to treat analysis, 16/79 (20%) achieved a sustained viral response. A mean increase in CD4 count of 61x10⁶/L (+ 190) from baseline was noted in the sustained viral responses compared to a mean decrease in CD4 count of 79x10⁶ /L (+158) in the non-responders (p = 0.017).

Conclusions:   The sustained viral responses of 20% seen in our patients compares favorably with published data. The incidence of adverse events was low. In our cohort, we found that achieving a sustained viral response was associated with a significant rise in CD4 level of >50 cells, and failure to respond was associated with a fall in CD4 count. We conclude that anti HCV therapy may lead to immunological benefits in HIV/HCV patients as well as reducing their HCV related mortality and morbidity.

Keywords: HIV/HCV coinfection; Interferon; Ribavirin