Application of the Price-Volume Approach in Cases of Innovative Drugs Where Value-Based Pricing is Inadequate: Description of Real Experiences in Italy.

Several cases of expensive drugs designed for large patient populations (e.g. sofosbuvir) have raised a complex question in terms of drug pricing. Even assuming value-based pricing, the treatment with these drugs of all eligible patients would have an immense budgetary impact, which is unsustainable also for the richest countries. This raises the need to reduce the prices of these agents in comparison with those suggested by the value-based approach and to devise new pricing methods that can achieve this goal. The present study discusses in detail the following two methods: (i) The approach based on setting nation-wide budget thresholds for individual innovative agents in which a fixed proportion of the historical pharmaceutical expenditure represents the maximum budget attributable to an innovative treatment; (ii) The approach based on nation-wide price-volume agreements in which drug prices are progressively reduced as more patients receive the treatment. The first approach has been developed in the USA by the Institute for Clinical and Economic Review and has been applied to PCSK9 inhibitors (alirocumab and evolocumab). The second approach has been designed for the Italian market and has found a systematic application to manage the price of ranibizumab, sofosbuvir, and PCSK9 inhibitors. While, in the past, price-volume agreements have been applied only on an empirical basis (i.e. in the absence of any quantitative theoretical rule), more recently some explicit mathematical models have been described. The performance of these models is now being evaluated on the basis of the real-world experiences conducted in some European countries, especially Italy.