FORMULARY MANAGEMENT OF ACE-INHIBITORS

An increasing number of ACE inhibitors have become available in recent years. Because these agents are all similar, careful scrutiny is requ ired in order to determine specific advantages of particular agents wh en making formulary decisions. Differences between agents with regard to structure and tissue specificity have been identified, but the clin ical relevance of these differences is not clear. ACE inhibitors vary greatly with regard to bioconversion, distribution and elimination Dis ease states such as congestive heart failure (CHF) and hepatic or rena l insufficiency may affect the disposition of specific ACE inhibitors. These agents may differ substantially in duration of action, and ACE inhibitors that are given once daily may optimise patient compliance a nd decrease costs. ACE inhibitors have been extensively studied in pat ients with hypertension, CHF or nephropathy, and following myocardial infarction (MI). Differences in efficacy between agents are often a re sult of variations in study design, or because nonequipotent dosages w ere compared. It is likely that the benefits of ACE inhibitors are cla ss effects, and it is probably reasonable to use an agent even if larg e scale clinical trials have not been performed with that particular d rug. Few differences have been found between ACE inhibitors with regar d to adverse effects or drug interactions, and these factors are of mi nor importance when making formulary decisions. Cost and availability may vary among agents, and will depend on geographical location and in stitution-specific purchasing contracts. ACE inhibitors have shown pos itive effects on quality of life when compared with agents of other cl asses. Quality-of-life studies that have directly compared ACE inhibit ors have produced conflicting results. In the setting of hypertension, cost-effectiveness evaluations typically find that the newer, longer- acting ACE inhibitors provide the greatest financial benefit. Differen ces in cost effectiveness in the post-MI patient population are typica lly the result of variations in protocol design, including duration of treatment and nondrug costs. ACE inhibitors are fairly homogeneous an d selection between agents can be difficult. Clinical efficacy, time c ourse of action, and cost are the primary concerns in selecting agents for inclusion on a formulary.