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# FDA Sued Over Orenitram Orphan Drug Denial
- URL: https://www.fdaweb.com/fda-sued-over-orenitram-orphan-drug-denial/
- Published: 2017-08-10T12:00:00.000Z
- Updated: 2026-09-14T22:40:33.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5139351

United Therapeutics is suing FDA in DC federal court over the agency’s denial of orphan drug exclusivity for the company’s Orenitram (treprostinil) extended-release tablets to treat pulmonary arterial hypertension (WHO Group 1) to improve exercise capacity. Attorney **Kurt Karst** (Hyman, Phelps & McNamara) [writes](http://www.fdalawblog.net/fda%5Flaw%5Fblog%5Fhyman%5Fphelps/2017/08/united-therapeutics-sues-fda-after-agency-denies-orphan-drug-exclusivity-for-orenitram.html?ref=fdaweb.com) in his firm’s *FDA Law Blog* that the company says “FDA has unlawfully denied Orenitram its statutorily mandated exclusivity.” (The law firm represents United Therapeutics in this action.)

The company says FDA indicated that for it to receive orphan drug exclusivity, it would have to demonstrate that oral treprostinil is clinically superior to the other treprostinil formulations by means of greater efficacy, greater safety, or a major contribution to patient care.

Karst writes that the agency’s heightened standard for demonstrating clinical superiority to obtain orphan drug exclusivity was at the heart of a 9/2012 lawsuit filed by Depomed over Gralise (gabapentin) tablets. Depomed won that suit, he says.

In that case, according to Karst, the judge held that the law requires FDA to grant orphan drug exclusivity if two specific conditions are met — the drug has been designated for a rare disease or condition, and FDA has approved a marketing application for the drug. Rather than appeal the Depomed decision, Karst writes, the agency published a 12/23/14 “clarification of policy” saying that the court decision was limited to Gralise and that FDA will continue to apply its clinical superiority regulatory paradigm when considering orphan drug exclusivity.

United Therapeutics says that because FDA admitted that Orenitram was properly designated as an orphan drug to treat pulmonary arterial hypertension, the statute dictates that it be granted seven-year exclusivity from the date of approval, until 12/20/20.

The suit says that FDA violated the Administrative Procedures Act by making a decision that was arbitrary and capricious, an abuse of discretion, outside its legal authority, and otherwise not in accordance with the law.