Reference Pricing as a Deterrent to Entry: Evidence from the European Pharmaceutical Market

External reference pricing (ERP), the practice of benchmarking domestic drug prices to foreign prices, generates an incentive for firms to withhold products from low-income countries. Using a novel moment inequality approach, we estimate a structural model to measure how ERP policies affect access to innovative drugs across Europe. We find that ERP increases entry delays in eight low-income European countries by up to one year per drug. The European Union could remove these delays without replacing ERP by compensating firms through lump-sum transfers at the cost of around €18 million per drug. (JEL L13, L51, L65)