Successful HCV eradication and inhibition of HIV replication by intravenous silibinin in an HIV-HCV coinfected patient

INTRODUCTION: The efficacy of antiviral therapy with pegylated interferon (PEGIFN) plus ribavirin (RBV) in patients with HIV and hepatitis C virus (HCV) coinfection is limited. Intravenous silibinin (ivSIL), a milk thistle extract with proven antiviral effects represents a novel therapeutic strategy for virological nonresponders.

METHODS: We report a case of an HIV-HCV coinfected patient, who has not responded to a prior course of PEGIFN-α2a (180 μg/week/s.c.) and RBV (1000 mg/day/p.o.). Testing for IL-28β small nucleotid polymorphism revealed the nonfavourable genotype T/T. Antiretroviral therapy was not prescribed because the patients presented with well-preserved CD4+ cell counts and low HIV-RNA levels. She received retreatment with ivSIL for two weeks followed by PEGIFN/RBV combination therapy starting at week 1.

RESULTS: After 2 weeks of ivSIL therapy both HCV-RNA and HIV-RNA become undetectable. On ivSIL monotherapy we noticed a trend towards an increase of CD4+ cell counts and a decrease of HIV-RNA. After 16 weeks PEGIFN+RBV was discontinued due to patients wish because of adverse events. HCV-RNA was still negative 24 weeks after cessation of therapy, while HIV-RNA returned to baseline levels.

CONCLUSION: ivSIL may represent a potential treatment option for retreatment of HIV-HCV coinfected patients nonresponding to PEGIFN+RBV combination therapy. Further investigations on the possible beneficial effects of ivSIL on CD4+ cell counts and HIV-RNA levels are necessary.