In vitro and in vivo antiviral activity and resistance profile of the hepatitis C virus NS3/4A protease inhibitor ABT-450.

The development of direct-acting antiviral agents is a promising therapeutic advance in the treatment of hepatitis C virus (HCV) infection. However, rapid emergence of drug resistance can limit efficacy and lead to cross-resistance among members of the same drug class. ABT-450 is an efficacious inhibitor of HCV NS3/4A protease, with 50% effective concentration values of 1.

Similar safety and efficacy of once- and twice-daily lopinavir/ritonavir tablets in treatment-experienced HIV-1-infected subjects at 48 weeks.

Objectives: To compare the safety and antiviral activity of once (QD) or twice (BID) daily lopinavir/ritonavir (LPV/r) in combination with investigator-selected nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) in treatment-experienced subjects.

Methods: Subjects failing treatment with HIV-1 RNA > 1000 copies per milliliter received LPV/r tablets 800/200 mg QD (n = 300) or 400/100 mg BID (n = 299) with investigator-chosen nucleoside/nucleotide reverse transcriptase inhibitors. Efficacy was determined by the intent-to-treat time to loss of virologic response (ITT-TLOVR) algorithm.