Phase III study results show that investigational RLX030 (serelaxin) reduced all-cause mortality in patients with acute heart failure (AHF). The six-month RELAX-AHF study shows that RLX030 reduces the number of deaths in patients with this disease, which has a higher mortality rate than most other cardiovascular diseases.

The study had two primary endpoints using different scales to measure reduction in dyspnea, only one of which reached statistical significance. Dyspnea, or shortness of breath, is the most common symptom of AHF. RLX030 was well tolerated in the study.

RELAX-AHF was a phase III clinical trial to investigate the efficacy and safety of RLX030 for the treatment of AHF. It was a randomized, double-blind, placebo-controlled study involving 1,161 patients in 11 countries. In the study, RLX030 was given on admission to the hospital in the form of an intravenous infusion for up to 48 hours in addition to loop diuretics and other medicines and was compared to placebo on top of standard of care treatment for AHF.

The study will be presented at the American Heart Association (AHA) congress in Los Angeles in November, 2012. Novartis will initiate discussions of the results of this single phase III study with health authorities worldwide shortly.

Heart failure is a disease in which the heart is unable to supply enough blood to meet the body's needs. Around half of all patients die within five years of diagnosis, particularly as a result of acute episodes in which their symptoms suddenly become worse and urgent hospital treatment is needed. Acute heart failure (AHF) places an enormous burden on healthcare systems and accounts for around two million hospitalizations each year in the EU and US.

RLX030 is the first in a new class of medicines and is a recombinant form of the human hormone relaxin-2 which occurs naturally in both men and women. In women, levels of relaxin-2 rise to support important physiological changes during pregnancy. Serelaxin acts by relaxing the blood vessels, leading to reduced stress on the heart and kidneys in both men and women.