July 11, 2017
By Mark Terry, BioSpace.com Breaking News Staff
San Diego, Calif.-based Arena Pharmaceuticals ’ shares rocketed after positive data was announced from its Phase II clinical trial of a drug for pulmonary arterial hypertension (PAH).
Arena reported that in a trial comparing ralinepag to placebo, those on ralinepag improved by 29.8 percent in pulmonary vascular resistance (PVR) compared to placebo, and 20.1 percent improvement in PVR compared to baseline. Adverse events were consistent with other prostacyclin treatments for PAH, including headache, nausea, diarrhea, jaw pain and flushing.
PAH is a rare but deadly disease that is marked by constriction of the arteries of the lungs—essentially high blood pressure in the lungs. It can potentially lead to heart failure. Its symptoms include shortness of breath and fatigue.
There are a number of drugs already on the market for PAH, most notably Actelion ’s Opsumit and Uptravi. Johnson & Johnson acquired Actelion last year for $30 billion. Ralinepag works similarly to Uptravi.
Leerink Partners in May projected peak sales of ralinepag, if approved, at $1.1 billion.
Reuters notes, “Arena was originally betting on an obesity pill called Belviq as its main drug but tepid sales and poor adoption led it to negotiate an agreement with partner Eisai Co., Ltd. , which acquired the rights to Belviq earlier this year.”
As a result of that failure, the company made significant staffing cuts and restructuring.
“The positive outcome of this Phase II trial in a contemporary PAH patient population is an important milestone in the development of ralinepag for the treatment of patients suffering from this grievous illness,” said Preston Klassen, Arena’s executive vice president, Research and Development, and chief medical officer, in a statement. “It is exciting to see the positive nonclinical pharmacological profile translating into potentially the first oral prostacyclin therapy that may approach consistent therapeutic levels without the complexity of parenteral (IV) therapy. These data give us confidence to move expeditiously toward a Phase III clinical program.”
Arena Therapeutics are currently trading at $27.54. On July 10, shares traded for $18.39.
Jeremy Owens, writing for MarketWatch, noted, “Arena stock topped $25 in after-hours trading immediately following the announcement, after closing with a 4.5 percent decline at $18.39; Arena shares have not hit $25 in regular trading since 2015.”
Ralinepag (APD811) is an oral, selective IP receptor agonist that targets the prostacyclin pathway. The drug was discovered and developed in-house. The company believes it has the potential to be the best-in-class for PAH based on the potency of vasodilation, inhibition of proliferation of vascular smooth muscle cells, and inhibition of platelet aggregation.
“PAH is a complex and serious disease, often with a poor prognosis despite the use of currently available treatments,” said Vallerie McLaughlin, the Kim A. Eagle MD Endows Professor of Cardiovascular Medicine at the University of Michigan and Director of the Pulmonary Hypertension Program, in a statement. “The results of this Phase II study of ralinepag, in patients already receiving, in most cases, multiple background therapies, showed a clinically meaningful improvement in PVR, a well-established indicator of treatment benefit, believed to be correlated with long-term clinical outcomes in patients with PAH.”
