Willingness to pay for adverse drug event regulatory actions

Regulatory requirements for the pharmaceutical industry have become increasingly demanding with respect to the safety and effectiveness of drugs.

The objective of this study was to determine the willingness to pay (WTP), of both the Dutch general public and dialysis patients, for regulatory requirements related to reducing the risk of pure red cell aplasia (PRCA) associated with epoetin alpha use.

A survey was carried out in April 2009. The Dutch general public (n = 422) was approached through a survey sampling agency. Patients (n = 112) were included through several Dutch dialysis clinics because they are often treated with epoetin alpha and therefore were expected to have a higher WTP than the general public. The survey aimed to determine the WTP for reducing the risk of PRCA in epoetin alpha users from 4.5 to 0 per 10 000 patients per year, based on regulatory actions that have been taken by the European Medicines Agency (EMA). WTP was determined via a payment scale and an open-ended follow-up question. Patients were asked how much extra per year they would be willing to pay for their basic healthcare insurance. We used two censored regression models to test the association between WTP and a set of independent variables: a Tobit model with the stated WTP as the dependent variable and an interval regression model with the interval between the lower and upper bounds of the payment scale as the dependent variable.

The patients' mean WTP was significantly higher (€46.52) than that of the general public (€24.40). The Tobit model showed significant associations (α = 0.05) with WTP for dialysis patients, risk perception and respondents' opinions on costs of healthcare. The interval regression model showed significant associations with WTP for the same variables as the Tobit model and for one additional variable (risk aversion). Income did not significantly affect WTP. A scenario with a 10-fold larger risk reduction did not increase WTP significantly.

This study is, as far as we know, one of the first attempts to analyse the WTP for drug regulation and should in future be used in studies of the societal costs of drug regulation for epoetin alpha use. Our results indicate that the Dutch general public, especially Dutch dialysis patients, are willing to pay limited amounts to reduce the risk of serious adverse events associated with drug use.