Impacts of Patent Expiry on Daily Cost of Pharmaceutical Treatments in Eight OECD Countries, 2004-2010

Variability in regulatory frameworks, industrial policy, physician/pharmacy autonomy, brand/generic distinctions, and the practice of medicine contribute to ambiguous interpretations of cross-country pharmaceutical cost comparisons. Here, we report cross-country comparisons that: (i) focus on ten therapeutic classes experiencing patent expiration and loss of exclusivity 2004-2010 in eight industrialized countries; (ii) convert revenues and unit sales to cost per day of treatment and number patient days treated using the World Health Organization's Defined Daily Dosage metrics; (iii) compare patterns in costs per day of treatment with price index measures based on average price per day of treatment for each molecule computed over all molecule versions; (iv) utilizing econometric methods, model and quantify various factors affecting variations in daily treatment price indexes such as national regulatory and reimbursement policy changes, physician/pharmacy autonomy, and other factors; and (v) simulate changes in expenditures by country and therapeutic class had counterfactual policies been implemented.