POTENCY AND ADHERENCE : IMPROVING HAART EFFICACY IN THE CLINIC * —

The available follow-up measurements of the efficacy of antiretroviral therapy (ART), tell us a great deal about the potency of various treatment regimens. Of particular importance is that the regimen be salvageable, ie, the necessary drugs are available for sequencing, to preserve further options. Of primary importance is whether the patient accepts and adheres to the therapy, since virologic success has been directly correlated to adherence. However, potency should not be compromised in the quest for simplified therapy. Several factors have been related to loss of adherence: younger age and unstable housing, increased alcohol consumption, and adverse events related to therapy (especially lipodystrophy syndrome and worsening of depression between month 4 and month 20). With regard to factors that might have the strongest influence on compliance and to what degree, AIDS patients and physicians have indicated that their perceptions differ. In a national survey of 1599 patients and 138 physicians, participants gave varying responses when asked about number of pills required daily, number of daily intakes, side effects, and the need for lifelong treatment. The number of pills, specifically, has been shown to be an important issue for predicting treatment outcome. (Advanced Studies in Medicine 2001;1(12):491-494) W ith currently available antiretroviral therapy (ART), we have considerably reduced HIV-related morbidity and mortality, but since we have not been able to completely control viral replication and therefore eradicate the disease, assessment of viral load and CD4 count endpoints are a crucial part of clinical trials. These shortand mid-term follow-up measurements tell us a great deal about the antiretroviral potency of various treatment regimens. In clinical practice, however, each regimen should be custom tailored to the individual patient, and inherent in that regimen should be the salvageability, ie, having the necessary drugs available for sequencing, to preserve further options. In addition, provisions for durability and atoxicity (ie, low long-term levels of toxicity) must also be taken into account. Further, drugs must be affordable and accessible. Adequate consideration of these issues would provide long-term clinical benefit for the patient through immunologic and virologic control. We have already learned much about delaying disease progression by inhibiting viral replication and by using regimens of different potencies to achieve active drug concentrations in the plasma, in the cells, and in various compartments. In addition, we selectively use regimens to prevent viral resistance. Of primary importance, however, is whether the patient accepts and adheres to the therapy, since lack of adherence represents the greatest barrier to successful ART. Virologic success has been directly correlated to adherence. Paterson et al examined the relationship between level of adherence and virologic outcome in a group of HIV-infected patients taking protease inhibitor (PI) therapy and found that adherence ≥95% optimized the virologic outcome for these patients. Yet PROCEEDINGS