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# FDA Denies Tyvaso DPI Petition
- URL: https://www.fdaweb.com/fda-denies-tyvaso-dpi-petition/
- Published: 2022-05-23T12:00:00.000Z
- Updated: 2026-09-14T17:45:39.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5151874

FDA has denied a 7/8/21 petition submitted by Lassman Law+Policy on behalf of an unnamed client asking that the agency take four restrictive actions related to a United Therapeutics Corporation NDA for Tvvaso DPI (treprostinil) inhalation powder. The agency denial [letter](https://downloads.regulations.gov/FDA-2021-P-0714-0008/attachment%5F1.pdf?ref=fdaweb.com) says the drug’s risks are adequately characterized by the available safety data and are appropriately addressed in the labeling. FDA also maintains that a Contraindication, Boxed Warning, or Risk Evaluation Mitigation Strategy sought in the petition should not be included in the labeling. Additionally, the letter indicated that the agency 5/23 approved the Tyvaso NDA for treating pulmonary arterial hypertension (PAH; WHO Group 1) and treating pulmonary hypertension associated with interstitial lung disease (PH-ILD; WHO Group 3) to improve exercise ability.