A PILOT-STUDY TO EVALUATE THE FEASIBILITY OF USING WILLINGNESS-TO-PAYAS A MEASURE OF VALUE IN CANCER SUPPORTIVE CARE - AN ASSESSMENT OF AMIFOSTINE CYTOPROTECTION

The most commonly used method for pharmacoeconomic studies has been th e cost-effectiveness analysis (CEA), where the outcome is expressed as an incremental cost per unit of effectiveness (e.g. quality-adjusted life years). Although CEA is a valuable tool for identifying therapies that are more effective and less expensive, deficiencies develop when a given treatment is both more expensive and more effective. An alter native that has not been investigated in the oncology setting is the w illingness-to-pay (WTP) method. In this pilot study, a WTP strategy wa s utilized to estimate the value that the Canadian tax-paying public p uts on amifostine, a new cytoprotective agent that reduces the risk of chemotherapy-induced toxicity. The method of WTP was used within the framework of a classical cost-benefit analysis to estimate the net cos t or benefit of prophylactic amifostine in patients with ovarian cance r who were receiving chemotherapy. This included direct costs for amif ostine administration and hospital savings secondary to the reduced in cidence of antineoplastic toxicity. A random sample of 50 Canadian tax payers were interviewed to ascertain their maximum WTP for the new dru g. The WTP survey instrument was simple to administer and easily under stood by participants. Respondents stated that they would be willing t o pay an average of $Can3,476 (95% confidence interval = $Can2,275 to $Can4,676) as an income lax increase to be paid over their lifetime fo r the value offered by the product. The benefit was then subtracted fr om the overall cost of amifostine ($Can3,826). This produced a net cos t of $Can350 per patient (95% confidence interval = -$Can850 to $Can1, 551), suggesting a situation of cost neutrality. WTP as a measure of v alue for oncology products is feasible and should be considered for fu ture economic evaluations, The strategy is currently being used at thi s institution to determine the net societal cost or benefit of other c ancer supportive care therapies, such as epoetin-alfa.