Background: Canada's Patented Medicine Prices Review Board (PMPRB) uses external and internal reference pricing (IRP) to regulate patented drug list prices. PMPRB has changed external reference countries from 7 to 11 to include countries with prices closer to the OECD median. We examined the impact on the list prices for patented medicines had the amendment been implemented from 2013.

Methods: Using IQVIA MIDAS® quarterly sales data, we selected branded products that were launched in Canada in 2013–2018. The list price for each product in each country was calculated as its average annual price during the 3rd year post Canadian launch. The median international price (MIP) was the median of the list prices of PMPRB7 (MIP7) and PMPRB11 (MIP11). We assumed the same IRP would be (scenario 1) or would not be used (scenario 2).

Results: Among the selected 400 products, 80.3 % (321) had MIP7 and MIP11 (launched in at least one reference country); 18.3 % did not have MIP11. The total current expenditures were $7,134.4 M. In scenario 1, MIP11 would not be binding for most products and expenditures would decline only by 0.7 %. If IRP were abolished, expenditures might decline by 14.1 % if the launching sequence would not change.

Conclusions: MIP11 might not be binding for most medicines. The impact depends on whether to retain the IRP and approaches taken for medicines without MIP11.