Predicting Value and Price of Orphan Drugs: A Comparison Across Europe and the US

OBJECTIVES: Successfully forecasting the value and price of novel orphan drugs is complicated by the lack of sufficient evidence and/or appropriate comparators. This research aimed to determine the accuracy of a value-price model to forecast the price of an orphan product across different payer types.

METHODS: To forecast price of burosumab (an X-linked hyperphosphatemia treatment) in Italy, Spain and the US, 8 analogues assessed since 2015 with various indications, launch sequencing, and price were selected. A MCDA model with key attributes reflecting payer drivers for orphan products was developed. HTA and regulatory documents were used to derive value scores for each product. Different definitions for launch, reimbursed and current prices were applied per market and the annual cost of analogues was calculated. Analogue value score was plotted against annual cost on a linear regression, which was used to forecast burosumab price in each market. Forecast prices were compared to actual prices.

RESULTS: Value scores were driven by different key drivers across different payer types. Value scores and ranges were lowest for Spain (73%-45%, range=28) followed by Italy (69%-36%, range=33) and then the US (77%-41%, range=36). Nusinersen had the highest value score in all countries. Spanish data were limited and was excluded from regression analysis. There was a weak value-price relationship with all price types (Italy: R²=0.16–0.19; US: R²=0.04–0.08). However, burosumab predicted price was highly accurate (100%=highest accuracy) compared to actual price, with reimbursed price most accurate in the US ($249,865 vs $253,650; 98.5%; range=73.4%–98.5%) and launch price most accurate in Italy ($283,984 vs $262,917; 92.6%; range=91.6%–92.6%).

CONCLUSIONS: Analyses demonstrated that a value-price relationship can be used for price forecasting. However, correlation strength and accuracy maybe unrelated. Confidential discounting and segmented payer perceptions are limitations. Further research across different indications, analogues and markets is required.