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# Catalyst to Appeal Loss in Firdapse Orphan Drug Case
- URL: https://www.fdaweb.com/catalyst-to-appeal-loss-in-firdapse-orphan-drug-case/
- Published: 2020-09-30T12:00:00.000Z
- Updated: 2026-09-14T16:30:57.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5147771

Catalyst Pharmaceuticals says it will appeal to the 11th Circuit Court of Appeals a ruling by a Florida federal court granting summary judgment to FDA and Jacobus Pharmaceutical and dismissing Catalyst’s case involving orphan drug exclusivity for its Firdapse (amifampridine). In its [decision](20389782-0--9783.pdf), the district court accepted the report and recommendations filed with the court by a magistrate judge.

The Catalyst [suit](https://www.globenewswire.com/news-release/2020/09/29/2100971/0/en/Catalyst-Pharmaceuticals-Announces-Ruling-on-Lawsuit-against-the-FDA-and-Intent-to-Appeal.html?ref=fdaweb.com) challenged FDA’s approval of Jacobus’ Ruzurgi (amifampridine) for orphan drug status due to the agency’s earlier approval of Firdapse for orphan drug exclusivity. Catalyst argued that the FDA approval of Rusurgi violated Catalyst’s orphan drug exclusivity and also that FDA violated its labeling requirements in approving Ruzurgi.

The magistrate judge recommended dismissing the Catalyst case because the language of a section of the Orphan Drug Act is ambiguous and that FDA’s interpretation of that section and of the labeling requirement was reasonable.