The choice of pharmacoeconomic study design during drug development--part 2

Pharmaceutical manufacturers are faced with the challenge of when and how to conduct pharmacoeconomic (PE) evaluations to satisfy formulary decision-makers. To illustrate the usefulness of decision analysis for strategic planning in drug development, a model was created to compare the cost-benefit of three PE design options: (1) add-on to a phase III safety and efficacy randomized controlled clinical trial (RCT), (2) stand-alone phase IIIb trial and (3) a phase IV observational study. Hypothetical data on the cost of performing each type of study, the probability of a conclusive PE evaluation and the 5-year sales potential of a cost-effective product were incorporated into the model. At a discount rate of 7%, the incremental net benefit of a phase IIIb PE study was 4.2 million Canadian dollars compared to a phase III RCT and 10.5 million Canadian dollars compared to a phase IV study. The incremental net benefit of a stand-alone phase IIIb trial compared to an add-on phase III design was negligible when the formulary percentage of total sales was 25% and the discount rate 10%. Although the data used to demonstrate the model were hypothetical, decision analysis can be a useful tool for preparing a sensible development strategy or uncovering deficiencies in an existing plant.