Monitoring Antiviral Therapy:
The goals of antiviral therapy are to enhance immunity and delay or prevent clinical advancement to symptomatic disease without inducing important side effects or selecting for drug resistant virus. Currently, the best marker of a drug’s activity is a decrease in the viral load.
Ideally, before initiating treatment, the viral load and the CD4 cell count should be checked and the viral load test then repeated after approximately four weeks of treatment. If the patient is beginning a regimen that includes two to three drugs for which the patient’s virus does not appear to be resistant, it is expected that the amount of virus should decrease by at least hundredfold during this interval i.e., 4 weeks. The ultimate goal is for the viral load to decrease to undetectable levels which should occur by approximately 24 weeks. Those that are not having an appropriate response to therapy need to be questioned to make sure that they are taking their medications correctly, and if not, why. If the viral load is not going to undetectable levels and the patient is taking the medications correctly, then it is likely that there is a resistant virus to some of the medications. Drug-resistance testing then should be performed and the patient should be managed as described in the next section. Continue reading