Inhaled Tyvaso for PAH is Safe, Well Tolerated by Patients, Study Shows

Tyvaso (treprostinil sodium), a drug approved for enhancing exercise capacity in patients with pulmonary arterial hypertension (PAH), was reported in a recent study to be well tolerated and safe in routine clinical use.

The study, “An observational study of inhaled-treprostinil respiratory-related safety in patients with pulmonary arterial hypertension,” was published in the Pulmonary Circulation.

Tyvaso, an inhaled prostacyclin, was approved by the U.S. Food and Drug Administration (FDA) in 2009 to improve exercise capacity in patients with PAH (in the World Health Organization’s group 1 PAH). But the drug’s respiratory-safety profile associated with routine clinical use of inhaled Tyvaso required further explanation.

Researchers set out to characterized the drug’s respiratory-safety profile with help from a large, representative sample of patients with WHO group 1 PAH. The long-term prospective and observational safety clinical trial (NCT01266265) enrolled 1,333 patients from 94 centers throughout the U.S.  The study was called “Study of Incidence of Respiratory Tract AEs in Patients Treated With Tyvaso Compared to Other FDA Approved PAH Therapies (Aspire).”

The primary objective aimed to describe the type and incidence of respiratory-related adverse effects likely associated with current or recent treatment with inhaled Tyvaso. The secondary objective was to compare the incidence of respiratory-related adverse effects in patients treated with inhaled Tyvaso (666 patients) with those experienced by patients who used other FDA-approved PAH therapies (667 patients).

From the group of patients treated with inhaled Tyvaso, 403 patients (61%) registered 1,281 respiratory-related adverse effects. From the control group, 388 patients (58%) reported 1,295 respiratory-related negative effects.

The most common adverse respiratory issues included cough, throat irritation, nasal discomfort, and hemoptysis (coughing up of blood). Those events occurred at higher numbers per patient-year of exposure in the inhaled Tyvaso group than in the control group.

The overall results showed that inhaled Tyvaso was well tolerated by PAH patients in routine clinical care with fewer than 1 percent of patients discontinuing treatment due to adverse effects.

“Cough and throat irritation occurred at a higher rate in the inhaled-treprostinil group than in the control group, which was expected, given the administration route and pharmacological effects,” the team concluded in the report.  “Importantly, the overall rate of respiratory AEs did not differ between the inhaled-treprostinil and control groups. Respiratory-related AEs occurring during routine clinical use of inhaled treprostinil are consistent with its known safety profile.”