AstraZeneca’s blockbuster diabetes drug Farxiga led to significant reductions in the risk of hospitalisation and death in people with all types of heart failure, according to study data released on Saturday, opening the door to a substantial increase in patients who could benefit.

The drug belongs to a class of medicines called SGLT2 inhibitors that were initially approved to treat type 2 diabetes. Since then, the drugs have been shown to benefit patients with chronic kidney and heart disease and prevent heart attacks.

Farxiga is the first heart failure medication to show mortality benefit across all forms of heart failure, the company said.

Detailed data from a study called ‘DELIVER’ evaluating Farxiga in patients with a form of heart failure characterised by mildly reduced or preserved ejection fraction was presented at the European Society of Cardiology congress in Barcelona. Ejection fraction measures the heart’s ability to pump oxygen-rich blood into the body.

Farxiga met the study’s primary goal, inducing a statistically significant reduction in the risk of hear-related death, heart failure hospitalisation and urgent heart failure visits by 18%.

Assuming regulators endorse broader heart failure use based on this data, Farxiga’s addressable patient population will jump by 50%, said Ruud Dobber, who leads AstraZeneca’s biopharma business.

Eli Lilly and Co and Boehringer Ingelheim’s rival drug Jardiance performed similarly in study involving similar patients last year.

A pooled analysis of DELIVER and another trial involving about 11,000 heart failure patients combined showed Farxiga reduced the risk of death from cardiovascular causes – including heart attacks – by 14%, and death from any cause by 10%. The drug also cut the risk of hospital admissions for heart failure by close to a third.

Heart failure occurs when the heart muscle becomes unable to pump blood as efficiently as it should, and can cause a range of serious health problems and death. Of the estimated 64 million heart failure patients globally, roughly half have reduced ejection fraction, which is equal to or less than 40%. The remainder have mildly reduced or preserved ejection fraction.

Irrespective of low or high ejection fraction, the benefit of Farxiga was consistent, said Pardeep Jhund, professor of cardiology at the University of Glasgow who worked on the analysis.

Despite many available heart failure treatments, patients continue to have a poor prognosis, so initiating therapy instead of waiting for tests to determine ejection fraction is key. This analysis shows that there is no need to wait, Jhund said.

It also addresses doubts that patients at the higher ejection fraction (EF) spectrum – with an EF of around 65% or higher – would not derive the same benefit, concerns that arose with Jardiance trial data.

Last year, Farxiga generated just over $3 billion in sales. In 2022, it has had sales of about $1 billion each quarter.

This analysis pushes SGLT2 inhibitors to the forefront of heart failure therapy, said study co-author Scott Solomon, professor of medicine at Harvard Medical School, Brigham and Women’s Hospital.

Doctors will likely choose Farxiga or Jardiance based on availability and cost, which will “probably be more important than any potential differences between those therapies,” he said.