With inhaled version of Tyvaso, United Therapeutics sniffs a potential blockbuster

United Therapeutics had to jump through plenty of hoops to secure approval for Tyvaso DPI in the United States.

Now that the FDA has finally signed off on the inhaled dry powder version of the drug, United is set to reap hard-earned rewards for the drug that treats people with pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD).

Set to launch next month, the new delivery method promises to swell the market potential of the treatment that generated $483 million in sales last year. That’s the opinion of analysts at BTIG Research and Strategy.

“We estimate more than $1 billion in peak use of Tyvaso DPI in PAH and a potential $2 billion (plus) opportunity for PH-ILD, given the lack of competition and unmet need,” BTIG’s Robert Hazlett wrote in a note to clients in February.

Tyvaso won its original FDA approval in 2009 to treat PAH. Then in April of last year, it gained the PH-ILD indication, a game-changer for United as it added 30,000 to 100,000 potential new patients, according to BTIG.

With the ability to provide Tyvaso through the more convenient dry powder inhaler—which fits in the palm of the hand—United believes that more people with both conditions will be drawn to the product. There is no other approved medicine for PH-ILD. This is the first inhaled therapy for either indication.

“The convenience and portability of Tyvaso DPI may make it an important new option … with the potential for improving the quality of life for this patient population,” Shelley Shapiro, M.D., Ph.D., at the David Geffen UCLA School of Medicine Pulmonary Hypertension Program, said in a statement.

Tyvaso was poised for a launch of Tyvaso DPI early this year. But in October of 2021, it received its second complete response letter from the FDA. The regulator found a manufacturing problem at a “third-party” facility that conducts analytical testing on the drug. United assured the FDA that that the problem could be remedied quickly.  

Another potential complication mentioned in the CRL was a citizen petition, submitted to the FDA in July of 2021, which warned of the risk of bronchospasm.

The condition is noted as a risk factor with MannKind’s inhaled insulin treatment Afrezza. The company is United's manufacturing partner on Tyvaso. Bronchospasm has not cropped up in trials for Tyvaso DPI but the condition is listed as a potential side effect, with those with asthma or chronic obstructive pulmonary disease (COPD), at increased risk.