- Subject is currently taking or will require any drugs that are contraindicated or have significant pharmacokinetic interactions with study drugs during the course of the study. For complete information refer to the most current product label for locally approved prescribing information for lopinavir/ritonavir (Kaletra), efavirenz (Sustiva), tenofovir disoproxil fumarate (Viread), emtricitabine (Emtriva), co-formulated emtricitabine/tenofovir disoproxil fumarate (Truvada) and lamivudine (Epivir).