Roivant’s $14 million bet on a pulmonary hypertension drug from Bayer appears to have paid off as the inhaled med aced a phase 2 lung disease study.
After agreeing to a $294 million biobucks deal with Bayer for the soluble guanylate cyclase activator, mosliciguat, in 2024, Roivant wasted no time advancing the medicine into a phase 2 study.
The PHocus trial evaluated mosliciguat against placebo in 135 patients with pulmonary hypertension associated with interstitial lung disease (PH-ILD) spread across 20 countries. The results, which were unveiled at the European Respiratory Society International Congress in Barcelona on Tuesday, suggest the modest upfront fee was worth it.
The study hit its primary endpoint by demonstrating a placebo-adjusted reduction in pulmonary vascular resistance (PVR)—a measure of blood flow across the heart—of 56.3% at Week 16. The trial also met its secondary endpoints by showing a placebo-adjusted improvement in six-minute walk distance (6MWD) of 35.2 meters and a placebo-adjusted reduction in NT-proBNP—a biomarker of cardiac strain—of 53.2%.
There was more good news on the safety front, with incidence of cough—a well-known issue with inhaled prostacyclins used to treat PH—affecting just 12.1% of patients receiving mosliciguat compared to 18.2% of the placebo cohort.
The inhaled prostacyclin treprostinil is the only drug specifically approved for PH-ILD, marketed by United Therapeutics as Tyvaso and as Yutrepia by Liquidia. Roivant has previously touted mosliciguat as requiring just one daily inhalation, unlike other inhaled PH therapies, which require multiple inhalations at various points during the day.
Drew Fromkin, the CEO of Pulmovant—the biotech that Riovant set up to take mosliciguat forward—reiterated that the current treatment landscape for patients with PH-ILD is “sparse.”
“Our robust phase 2 PHocus study results, in conjunction with mosliciguat’s inhaled, once-a-day administration and potential first-in-class sGC activator profile, strongly position it as a potential single-agent treatment and combination therapy for patients with PH-ILD,” Fromkin said in a Sept. 8 release.
“PH-ILD is a disease as bad as some forms of cancer, with a median survival of just 1.5-2 years despite best-available standard of care,” Roivant’s President and Chief Investment Officer Mayukh Sukhatme, M.D., noted in the same release. “We wanted to see if we could make an impact in this terrible disease when we brought mosliciguat into Roivant.”
Two years ago, Roivant justified its decision to acquire mosliciguat by pointing to phase 1 results that tied the therapy to PVR reductions of around 38%. At the time, the company described these findings as “one of the highest reductions seen in PH trials to date.”
In this morning’s release, Sukhatme said Roivant’s hope had been that the phase 1 results “actually understated the potential of mosliciguat,” with the drug having the potential to produce “considerably more” benefits for patients when dosed chronically.
“These PHocus results proved that out as clearly as we could have hoped: a profound 56.3% placebo-adjusted PVR reduction—the largest PVR reported in any controlled pulmonary hypertension trial of any group,” he added.
“This data set puts mosliciguat in a league of its own on PVR reduction, 6MWD improvement, NT-proBNP % reduction, cough rate and ease of use,” Sukhatme concluded.
Based on the mid-stage results, Pulmovant confirmed today that it has already taken mosliciguat into a phase 3 study as part of a goal to “rapidly bring” the therapy to the around 200,000 patients in the U.S. and Europe who suffer from PH-ILD.