Relaxin shows favorable trends in treating acute heart failure
NEW ORLEANS—An interim analysis showed that relaxin, a naturally occurring peptide hormone that acts as a systemic and renal vasodilator, relieved the signs and symptoms of acute heart failure, according to a at a satellite symposium presentation Monday in conjunction with the American Heart Association (AHA) Scientific Sessions.

John Teerlink, MD, a professor of medicine at the University of California San Francisco and co-principal investigator, presented the interim analysis of the Phase II multicenter, randomized, double-blind, international Pre-RELAX AHF study.

The data from the first 209 patients enrolled in the trial demonstrated beneficial trends in acute heart failure (AHF) signs, symptoms and outcomes with no evidence of renal toxicity. Relaxin (from Corthera) appeared safe and well tolerated over a wide dose range.

“Compared to placebo, relaxin’s effect on the important endpoint of relieving dyspnea was apparent within six hours after start of treatment. These initial effects lasted up to 14 days after treatment, something not previously seen with other therapies for AHF,” Teerlink said.

Relaxin becomes elevated in pregnant women to modulate increases in renal and cardiac function that meet the increased hemodynamic demands. Patients experiencing acute heart failure also have an increase in relaxin, as the body tries to decrease artery pressure and improve function, Teerlink told Cardiovascular Business News.

The first notable improvement in the study came with the alleviation of dyspnea, within hours and out to 14 days.

“That was interesting,” Teerlink said, “but we wanted to see if there were more comprehensive trends associated with the drug.”

Investigators then teased out the data to determine if there were any changes in diuretic usage and if those changes were associated with improved or worsened kidney function. They found a trend in less use of diuretics in patients taking relaxin, while overall kidney function improved.

Researchers next found a trend in greater body weight loss from excess water in patients taking relaxin.

Another interesting finding, according to Teerlink, was that patients on relaxin improved enough to resume ACE inhibitor/beta-blocker therapy, which then improved their condition even further.

Teerlink said that these findings are important breakthroughs.

Co-principal investigator Marco Metra, MD, a professor of cardiology at the University of Brescia, Italy, also spoke at the symposium. “Patients with AHF remain a major clinical challenge with extremely high morbidity and mortality rates. Promising new agents such as relaxin are needed to treat these patients and improve their outcomes. The data from the Phase II study met the objectives of the proof-of-concept Pre-RELAX-AHF study, allowing the selection of the appropriate dose and endpoints for further study. Progression to the Phase III portion of the study is now clearly warranted.”