Thesis: In 2012, cost-effectiveness has been formally introduced in the French legislation as a criterion to determine the price of prescription drugs. Cost-effectiveness is requested to claim for reimbursement of drugs expected to provide a therapeutic benefit and to have a significant impact on Social Insurance budget. Cost-effectiveness estimates the incremental cost and effectiveness produced by an intervention in comparison to other interventions that could have been used. The thesis is an empirical analysis of delegation relationships in the regulation of reimbursed drugs in France. The thesis analyses three different applications of cost-effectiveness evaluation to highlight the issues surrounding the use of economic calculation and the risks that are associated with it through three questions: 1) does the cost-effectiveness evaluation expose the regulator to regulation capture? 2) Is the contribution of the cost-effectiveness evaluation enhanced in a regulatory framed process? 3) Could complementary evaluations enrich cost-effectiveness evaluation and favour its usage via the clarification of the issues surrounding the decision? The thesis documents the benefit provided by the introduction of the cost-effectiveness criteria. The actual risk of regulation capture could be limited through a more transparent process of evaluation and through a clarification of the objectives of the regulation.