Orphan Drug Approval in Canada, 1999-2022: A Cross-sectional Study.

The number of drugs for orphan indications has been increasing significantly in Canada and the federal government recently announced an investment of $1.5 billion dollars over 3 years primarily directed at helping to fund the cost of these drugs. There are claims and counterclaims about what percent of Food and Drug Administration (FDA) orphan drugs are available in Canada and how delayed these drugs are in being approved by Health Canada. This study uses FDA and Health Canada databases and data from three health technology assessment agencies and one drug bulletin to provide objective data about the percent of FDA approved drugs that were also approved by Health Canada, any delays in Canadian approval and the additional therapeutic value of new orphan drugs. Decisions about what drugs should be publicly covered and how long it took to make those decisions were not investigated. From 1999 to 2022, the FDA approved 326 new drugs for an orphan indication and Health Canada approved 231 (70.9%) for the same indication. The median time between FDA and Health Canada approval was 346 days (interquartile range [IQR] 181, 785). The percent rated as major improvements declined from 50% of the total in 2004-2008 to 13.6% in 2019-2022. These findings need to be taken into account as Canada develops an orphan drug policy and decides on criteria for funding this group of drugs. Specifically, when high quality evidence about the additional therapeutic value of orphan drugs is not available at the time of approval, risk sharing funding agreements with manufacturers should be put in place. Manufacturers should understand that if the results of post-market trials do not provide convincing evidence of value, funding will be withdrawn. Finally, the quality of any research plan should be used to prioritize candidates for federal funding.