Interferon+Ribivarin in 19 HCV/HIV Coinfected Hemophiliacs Reported at AASLD

Interferon+Ribivarin in 19 HCV/HIV Coinfected Hemophiliacs Reported at AASLD

In this small study of 19 HCV/HIV coinfected hemophiliacs, the researchers found virologic response was 32% which is about that seen (a little lower) in HIV negative HCV positive patients. In 2 large studies 38-43% sustained virologic response was seen. They also concluded therapy was safe. They did report non-significant CD4 decreases. Often CD4 absolute count can decrease but CD4 % remains the same. After IFN-RBV therapy is stopped CD4 count can return to baseline. Study authors reported expected decreases in platelets and hemoglobin. For 2 patients, their HIV viral load went from undetectable to detectable after IFN-RNV therapy started. There isn't a way to know the cause of this but it relates to a concern regarding d4T & AZT interaction with ribivarin. Most researchers do not think that this interaction is clinically meaningful but more conclusive in vitro studies are looking at that question. In several small clinical studies, it does not appear as though this interaction has had an effect on HIV viral load.

Efficacy of Interferon Plus Ribivarin Combination Treatment and Impact on HIV Infection in Hemophiliacs with Chronic HCV and Under HAART
(Silvia Sauleda, abstract 751)

This study looked at the safety & efficacy of IFN+RBV in hemophiliacs with chronic HCV & HIV coinfection. These results come from the AASLSD program book. 19 coinfected hemophiliacs were included and all were receiving HAART (NRTIs plus onr or two protease inhibitors and/or a NNRTI). The author reported cd4s were >400, HIV viral load was Ł10,000. Patients received IFN+RBV (3 MU/tiw, RBV 800-1200 mg/day) for 6 to 12 months depending on genotype and baseline HCV viral load. Baseline & monthly ALT levels, CD4 counts, HIV viral load, HCV viral load and blood counts were monitored.

Baseline ALT and HCV viral load was 164 ą 139 IU/ml and 6.4 ą 6.3 million copies/ml. 68% had genotype 1. One end-of-treatment responder has not yet completed post treatment follow-up. 18 patients have completed follow-up. 12 patients discontinued therapy at 6 months because HCV viral load above 5 million and were considered virologic non-responders. The other 6/18 (3 genotype 1, 2 genotype 2, , and 1 genotype 3) completed 12 months treatment and have remained HCV viral load undetectable for at least 6 months after stopping therapy. This is a sustained virologic response rate of 33%.

Changes in CD4 counts were not statistically significant, but a slight decrease in mean counts was seen in the first months. 8 patients with undetectable HIV viral loads at baseline remained so during follow-up, while 2 patients developed detectable viral load one month after treatment was started. Conversely, in 2 patients HIV viral load became undetectable after starting IFN+RBV. IFN can reduce HIV viral load after starting therapy but studies suggest viral load increases back to baseline.

Hemoglobin decreased significantly after 1 month (15 ą 1.2 g/dl vs 13.4 ą 1.3, p=0.001), and so did platelets (162,916 ą46,217 x 10⁶ to 156,636 ą 49,441, p=0.008). None of the patients, however, had to discontinue therapy for severe adverse affects, although all suffered from at least one minor adverse reaction (flu-like symptoms, weight loss, insomnia). No patients required changes in HAART regimen.

The authors concluded IFN+RBV was well tolerated in HIV+ hemophiliacs receiving HAART, and sustained response rates were similar to those seen in HIV negative patients. They also concluded IFN+RBV does not seem to have any significant effect on HIV replication or CD4 count.