Ralinepag Reduces PAH Patients’ Risk of Death, Phase 2 Trial Shows

Arena Pharmaceuticals’ ralinepag reduced the risk of pulmonary arterial hypertension patients dying, a Phase 2 clinical trial showed.

Temple University Professor Raymond Benza will present the results at the International Society for Heart and Lung Transplantation meeting in Nice, France, on April 14.  The four-day conference started April 11.

The title of Benza’s presentation is “Ralinepag, An Oral, Selective, Prostacyclin (IP) Receptor Agonist Consistently Improved Mortality Risk Scores Derived From PAH Registries Across Three Regions: Phase 2 Study Analysis.” In addition to working at Temple, he is chair of cardiovascular research at Allegheny General Hospital in Pittsburgh.

Ralinepag (APD811) is a selective prostacyclin receptor agonist. Prostacyclin is a substance produced by cells lining the walls of arteries and veins.It is a potent vasodilator, widening blood vessels so that blood flows better through them. It also inhibits platelet clumping and the growth of blood vessel muscle cells.

The therapy stays in the body for some time, increasing its effectiveness.

Arena developed it as an oral treatment, making it easier to use than other prostacyclin receptor agonists.

The 13-week trial (NCT02279160) compared ralinepag’s effectiveness with that of a placebo in 60 PAH patients. Researchers followed patients for 22 weeks after treatment.

The team used three scales to evaluate the treatment’s ability to reduce the risk of PAH patients’ death. The scores identify patients at the greatest risk of death, and show whether treatments can move patients into a lower-risk category.

“Patients receiving ralinepag experienced improvements in their mortality risk category,” Benza said.

“These positive data further highlight the potential of ralinepag as an effective treatment of PAH,” he said. “I look forward to determining the impact of ralinepag on clinical outcomes in the Phase 3 clinical program.”

Arena had previously announced key Phase 2 results. One finding was that ralinepag improved blood flood in lung arteries. Another was that it improved patients’ exercise capacity, as measured by the distance they could walk in six minutes.

Adverse events associated with the treatment were similar to the ones seen with other prostacyclin-based treatments, researchers reported.

Arena is also testing an ulcerative colitis treatment called etrasimod (APD334) and a compound known as APD371 for pain associated with Crohn’s disease.