Vicriviroc, a new CC-chemokine receptor 5 inhibitor for treatment of HIV: properties, promises and challenges.

Importance Of The Field: Although HIV has become a treatable disease with near to normal life expectancy, the quest for the development of better tolerated drugs with simple dosing schedules and a high barrier to the emergence of drug resistance remains. Vicriviroc is a small-molecule chemokine receptor antagonist that inhibits the binding of R5-tropic HIV-1 to host cells at the CC-chemokine receptor 5 (CCR5) co-receptor, thus, preventing viral entry. CCR5 inhibitors are believed to possibly decrease inflammation from the immune system and thereby offer additional properties further to their antiretroviral efficacy.

Areas Covered In This Review: This review is based on a PubMed search covering the years 2005 - 2010 for pharmacokinetic, pharmacological and clinical data of vicriviroc.

What The Reader Will Gain: In this review, the pharmacokinetic, pharmacological and clinical data of vicriviroc are presented. Moreover, the potential role of vicriviroc in the growing HIV armamentarium is discussed.

Take Home Message: Vicriviroc is being developed to be administered in combination with a ritonavir-boosted protease inhibitor for patients with R5-tropic virus. Early clinical trials have established the safety of vicriviroc in both treatment-naive and -experienced R5-tropic HIV-1 infected individuals. Recently, two Phase III clinical trials in treatment-experienced patients failed to prove its superiority over available HIV medications. Phase III trials for treatment-naive patients are still under planning. Clearly, more favorable study results are needed to move vicriviroc into drug registration and approval.