The Sun Will Come Up Tomorrow (or Will It)? FDA Issues Notification About Orphan Drug Exclusivity in Light of Recent Court Decision

Footnotes for this article are available at the end of this page.

Recently, the Food and Drug Administration published a Notification to clarify its policy about orphan drug exclusivity.1 The agency issued the announcement because the U.S. Court of Appeals for the 11th Circuit found that FDA erred in approving a drug product, in violation of the Orphan Drug Act. Learn more about another case involving orphan drug exclusivity and a general overview of the regulatory framework here.

The bottom line is that, while FDA agreed to comply with the 11th Circuit’s decision for the specific case, the agency said that it plans to continue its policy of applying “its regulations tying the scope of orphan-drug exclusivity to the uses or indication for which a drug is approved to matters beyond the scope of the order.”2

The Notification went into effect on January 24, 2023.


  • Both Jacobus Pharmaceutical Company and Catalyst Pharmaceuticals each had orphan-drug designation for the drug, amifampridine, for the treatment of Lambert-Eaton myasthenic syndrome (“LEMS”).
  • In November 2018, FDA approved Catalyst’s drug for the treatment of LEMS in adults.
    • FDA granted Catalyst’s drug orphan-drug exclusivity for the adult indication.
    • Shortly thereafter, FDA approved Jacobus’s drug for the treatment of LEMS in children.
    • FDA followed its longstanding rule, codified in its regulations (e.g., 21 C.F.R. § 316.31), that the orphan-drug exclusivity for Catalyst’s drug protected only the approved use or indication within the designated disease (i.e., adult patients).
    • Catalyst sued FDA, challenging approval of Jacobus’s application, arguing that the statute prohibited FDA from approving Jacobus’s new drug application. Catalyst argued that the Orphan Drug Act required orphan-drug exclusivity to extend to all uses or indications within the orphan-designated disease or condition, even uses or indications for which Catalyst had not received approval, such as the treatment of LEMS in children.
  • The district court found for FDA, holding that the agency reasonably interpreted the statute to tie orphan-drug exclusivity to the uses or indications for which the drug was approved.
  • On appeal, the 11th Circuit reversed, noting that the phrase, “same disease or condition” in the Orphan Drug Act, unambiguously foreclosed FDA’s interpretation. Therefore, orphan-drug exclusivity for Catalyst’s drug blocked FDA’s approval of Jacobus’s drug for all uses or indications within the orphan-designated disease (LEMS).
  • In its Notification, FDA stated that it intends to continue to apply its existing regulations linking orphan-drug exclusivity to the uses or indications for which the orphan drug was approved.
    • The agency said that the statutory text does not unambiguously require that orphan-drug exclusivity extend to the entire disease or condition for which a drug received orphan-drug designation, if the drug is only approved for some uses within that disease or condition.
    • FDA said that its regulations incentivize sponsors to continue to develop a drug for use in all persons affected by a rare disease or condition.

AGG Observations

  • FDA is not deterred by the 11th Circuit decision and concluded that it would stick by its interpretation of the Orphan Drug Act.
  • Notwithstanding the Catalyst ruling, FDA intends to apply its regulations at 21 C.F.R. Part 316 more narrowly than the 11th Circuit (i.e., the agency will limit the scope of orphan drug exclusivity to the specific uses or indications in the drug approval).
  • While FDA has clarified its position, sponsors now have alternative precedent to cite for potential challenges to this interpretation.
  • It looks like not much has changed in FDA’s mind, so further litigation should be expected; “tomorrow, tomorrow, I love ya, tomorrow, you’re always a day away.”


[1] Catalyst Pharms., Inc. vs. Becerra, 14 4th 1299 (11th Cir. 2021).

[2] 88 Fed. Reg. 4086 (Jan. 24, 2023).