Rationalize why HIV-positive patients are given a "cocktail" of drugs rather than a single antiviral agent to target the virus? Multiple Choice It is more cost-effective to give a combination of drugs simultaneously, rather than a single drug consecutively. Using several drugs together enhances the efficacy of each one. Each drug targets a different mechanism in the virus, collectively ridding the virus from the host. Reverse transcriptase, used by HIV for nucleic acid synthesis, cannot proofread for errors so mutations leading to multiple drug resistance are common.