1. 21 U.S. Code Part B. Drugs for Rare Diseases or Conditions. Vol §§360aa-§§360ff.
2. Spending for orphan indications among top-selling orphan drugs approved to treat common diseases;Chua;Health Aff (Millwood),2021
3. FDA approval, clinical trial evidence, efficacy, epidemiology, and price for non-orphan and ultra-rare, rare, and common orphan cancer drug indications: cross sectional analysis;Michaeli;BMJ,2023