A new heart failure drug has been so successful in early trials that it is being fast-tracked for human use.

Tests to compare a new angiotensin receptor–neprilysin inhibitor (LCZ696) with enalapril were stopped early because the “boundary for an overwhelming benefit” had been crossed.

LCZ696 is an investigational combination of valsartan, a drug which has been available for some time, and sacubitril (AHU-377), a drug developed by the same company (Novartis) in recent years.

The drug is designed for patients with congestive heart failure (CHF), a condition which weakens the heart to the point that is not able to pump blood efficiently around the body, and can lead to a number of fatal outcomes.

The new drug is a combination of two other drugs designed to lower blood pressure in different ways. The idea is that when blood pressure has been lowered, the heart will not have to pump as hard to get the blood to the body.

Enalapril is a well-understood Angiotensin-converting enzyme inhibitor, used as a first line treatment for heart failure in some cases. It works by blocking the body's innate response to stress in the veins and arteries, inhibiting the ability of the veins and arteries to contract, or for the heart to try and work around it.

The new compound acts through two pathways, blocking a different portion of the same pathway on which enalapril acts, as well as another enzyme which has not previously been medically inhibited. Experts say it is the full, long-term, effects of inhibiting this second pathway that will be the focus of further investigations.

The two were compared in cohort of 8000 CHF patients over 34 months, and showed a clearly reduced cardiovascular-related and all-cause mortality rate over the course of the study.

More details are available in the full report.