Context: In January 2023, Teva Pharmaceuticals Ltd. submitted an Abbreviated New Drug Application (ANDA) to the U.S. Food and Drug Administration (FDA) for a generic version of Firdapse in the U.S., ahead of the expiration of Catalyst Pharmaceuticals Inc.’s patents covering the drug in February 2037. In a notice letter to Catalyst, Teva alleged that those patents were invalid, unenforceable, and/or would not be infringed. In March 2023, Catalyst launched a patent dispute against Teva in the United States District Court for the District of New Jersey, alleging that its ANDA – if approved – would infringe on six Firdapse-related patents that it is currently licensing from Serb Pharmaceuticals S.A. Firdapse is a drug used to treat Lambert-Eaton myasthenic syndrome (LEMS), a rare auto-immune disease which impacts the signals sent from the nerves to the body’s muscles and causes weakness in the limbs. In 2024, Firdapse generated a net product revenue of over US$79 million – a 19.7% increase on the total revenue in 2023. In April 2023, it emerged that Catalyst was also suing Lupin Ltd. and Hetero Labs Ltd. (as well as its subsidiaries Annora Pharma Private Ltd. and Grace Consulting Services Inc.) for infringing the same six patents.
What’s new: Catalyst has settled its patent dispute with Teva, granting the latter a license to market Firdapse – subject to the FDA’s approval – no earlier than February 2035. The agreement is subject to review by the U.S. Federal Trade Commission (FTC) and Department of Justice (DOJ) (January 8, 2025 Catalyst press release).
Direct impact: Since announcing the settlement, Catalyst’s shares have gone up by 18%. This outcome comes in above expectations, according to analyst firm Oppenheimer & Co. The firm added: “Uncertainty around this topic had kept many on the sidelines and today’s update will facilitate investor interest in [Catalyst].”
Wider ramifications: The settlement is certainly a major boost for Catalyst’s Firdapse. However, the company is still embroiled in patent litigation over the drug with Hetero and Lupin. Only once those are concluded can we safely say Catalyst’s fight for Firdapse’s market protection will finally be over.
Florida-based Catalyst is a biopharmaceutical company focused on the treatment of rare diseases. Firdapse is one of its flagship drugs. Israeli Teva is a generic drugmaker. It is currently also embroiled in patent litigation with AstraZeneca over a diabetes drug in the UK.
The patents in this Catalyst dispute included:
- US Patent No. 10,626,088 (“Determining degradation of 3,4-diaminopyridine”)
As well as the following (which all bear the same title, “methods of administering 3,4-diaminopyridine”):
- US Patent No. 10,793,893
- US Patent No. 11,060,128
- US Patent No. 11,268,128
- US Patent No. 11,274,331
- US Patent No. 11,274,332
Lead attorney for Catalyst was Dennies Varughese, Pharm.D. at Sterne Kessler Goldstein and Fox. Charles H. Chevalier and Christine A. Gaddis at Gibbons P.C. also represented the plaintiff. Meanwhile, Teva was represented by Douglas R. Weider at Greenberg Traurig.
In a statement yesterday, Catalyst’s Co-Founder and Chairman Patrick McEnany said:
“We are pleased to have reached a resolution with Teva and believe this agreement solidifies Firdapse’s market exclusivity for many more years to come.”
The company has faced challenges over this drug before. After Firdapse was approved by the FDA in 2018, Catalyst was also granted exclusivity through November 2025. However, that same year a U.S. rival, Jacobus Pharmaceutical Company, also filed an NDA for Ruzurgi, another treatment for LEMS. To get around Catalyst’s exclusivity, the FDA separated Jacobus’s NDA into two parts: one for the treatment of LEMS in pediatric patients and the other for adult patients. Catalyst’s drug, on the other hand, is only for patients aged six and above. The FDA stated at the time that Ruzurgi did not breach Catalyst’s exclusivity because “the approval of the drug for pediatric patients constituted a different “indication or use” from the Firdapse approval for adult patients”.
Catalyst later filed a suit against the FDA over this approval, alleging that it violated the “same drug for the same disease or condition” restriction in the Orphan Drug Act. This law mandates that a drug which has officially been designated as a treatment for a rare condition is granted seven years of regulatory exclusivity after it receives FDA approval. During that time, the FDA cannot allow any other company to market the “same drug for the same disease or condition”.
This suit was initially dismissed in the Southern District of Florida. But, on appeal, the Court of Appeals for the Eleventh Circuit sided with Catalyst, ruling that the agency’s action was “arbitrary, capricious and not in accordance with the law.” That decision set a major precedent for orphan drug exclusivity in the U.S. (September 30, 2021 11th Circuit ruling).
Jacobus then filed a petition for a writ of certiorari (request for Supreme Court review) but that was denied in July 2022.