FDA Grants Approval to Tyvaso DPI: A New Inhalation Option for Pulmonary Hypertension Treatment

Groundbreaking Dry Powder Formulation Now Available for PAH and PH-ILD Patients

The U.S. Food and Drug Administration has approved Tyvaso DPI (treprostinil) inhalation powder, marking the first and only dry powder inhaler authorized for treating two serious forms of pulmonary hypertension. This development offers patients with pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD) a more portable and convenient administration method compared to existing options.

Understanding the Disease Burden

PAH, classified as WHO Group 1 pulmonary hypertension, is a life-threatening condition characterized by elevated blood pressure in the lung arteries. Approximately 45,000 Americans currently live with PAH, which progressively impairs the heart and lungs’ ability to function effectively. The disease has no known cure and requires ongoing pharmaceutical management.

PH-ILD represents a complication of interstitial lung disease, a category of conditions involving excessive lung tissue scarring. When pulmonary hypertension develops in ILD patients, outcomes deteriorate significantly. Current estimates suggest PH-ILD affects at least 15% of early-stage ILD patients (roughly 30,000 individuals in the U.S.) and may impact up to 86% of those with advanced fibrosis. This condition worsens exercise capacity, increases supplemental oxygen requirements, and reduces quality of life.

Clinical Evidence Supporting Tyvaso DPI

The FDA approval rests on data from the BREEZE trial, an open-label study involving 51 PAH patients already stabilized on Tyvaso Inhalation Solution. When these patients transitioned to Tyvaso DPI over three weeks, researchers documented safety, tolerability, and notable clinical improvements. Specifically, patients showed meaningful gains in six-minute walk distance—a key measure of exercise capacity—alongside superior device satisfaction and patient-reported outcomes compared to the solution formulation.

Supporting this primary trial, the TRIUMPH I study evaluated 235 PAH patients (predominantly NYHA Functional Class III) in a 12-week, placebo-controlled design. The most frequently reported adverse reactions with treprostinil were cough (54% vs. 29% placebo), headache (41% vs. 23%), throat irritation (25% vs. 14%), nausea (19% vs. 11%), and flushing (15% versus placebo rates).

Regarding PH-ILD, the INCREASE study demonstrated that inhaled treprostinil therapy effectively addresses this underserved patient population, providing clinical validation for this newer indication.

Product Characteristics and Mechanism

Tyvaso DPI delivers treprostinil, a synthetic prostacyclin mimetic, through an innovative dry powder delivery system small enough to fit in a patient’s palm. Unlike the nebulized solution formulation, the dry powder inhaler offers enhanced portability and simplified administration, potentially improving treatment adherence and patient quality of life. Both Tyvaso Inhalation Solution and Tyvaso DPI remain the only FDA-approved therapies specifically indicated for PH-ILD management.

Treprostinil functions as a pulmonary and systemic vasodilator. The medication works optimally within a 4-hour dosing window, allowing patients to adjust treatment timing around daily activities. Clinical experience with inhaled treprostinil typically involves concurrent endothelin receptor antagonist (ERA) or phosphodiesterase type 5 (PDE-5) inhibitor therapy.

Important Safety Considerations

Providers and patients should be aware of key safety parameters. Tyvaso DPI, like all inhaled prostaglandins, carries a risk of acute bronchospasm, particularly in patients with asthma, COPD, or other airway hyperreactivity conditions. Optimal management of reactive airway disease before and during Tyvaso DPI treatment is essential.

Both the inhaler and solution formulations inhibit platelet aggregation, potentially increasing bleeding risk. Concurrent use with diuretics, antihypertensives, or other vasodilators may precipitate symptomatic hypotension in susceptible patients. Additionally, specific drug interactions warrant attention: the CYP2C8 enzyme inhibitor gemfibrozil increases treprostinil exposure, while rifampin (a CYP2C8 inducer) decreases it—alterations that may modify clinical efficacy and safety profiles.

Limited data exist regarding treprostinil use during pregnancy and lactation. Safety and efficacy in pediatric populations have not been established. Among patients enrolled in efficacy trials, 268 participants (47.8%) were aged 65 years or older; observed treatment effects and safety profiles resembled those in younger cohorts, though cautious dose selection remains advisable in elderly patients with hepatic, renal, or cardiac impairment.

Clinical Commentary and Patient Impact

Dr. Shelley Shapiro, M.D., Ph.D., from the David Geffen UCLA School of Medicine Pulmonary Hypertension Program, emphasized that “the convenience and portability of Tyvaso DPI may represent an important new option for WHO Group 1 PAH and Group 3 PH-ILD patients, with potential to improve quality of life for this vulnerable population.”

Michael Benkowitz, President and Chief Operating Officer of United Therapeutics, noted that Tyvaso DPI represents “one of the easiest administration methods for prostacyclin therapy,” combining proven treprostinil efficacy with a handheld device format designed for patient accessibility.

Commercial availability is targeted for June 2022, with full launch activities underway to ensure patient access to this new treatment modality across healthcare settings.