By John Revill and John Miller
ZURICH (Reuters) - Novartis's heart failure drug Entresto failed a trial in a new use, the Swiss drugmaker said on Monday, calling into question billions of dollars in potential revenue and taking the shine off one of the company's biggest growth prospects.
The drug, already approved for reduced fraction heart failure, "narrowly missed" its objectives when tested on patients with preserved ejection fraction type of heart disease which affects 13 million globally, roughly half of all heart failure patients, the company said in a statement.
Twice-a-day Entresto has the potential for more than $3 billion annual sales for the current indication in patients whose heart muscles do not contract effectively, Novartis has said.
With a possible new indication in heart failure patients in whom the heart muscle contracts normally but the ventricles do not relax as they should, the Basel-based drugmaker saw total annual sales rising to as much as $5 billion. The failure in this trial in 4,822 patients puts the increased sales at risk.
"The trial narrowly missed statistical significance for its
composite primary endpoint of reducing cardiovascular death and total heart failure hospitalizations," Novartis said.
The Paragon HF trial compared Entresto against the older medicine valsartan, which Novartis sells under the brand name Diovan.
Entresto started out slow following its 2015 approval but has recently picked up momentum, with revenue rising about 80% in the first half of 2019 to $778 million globally as doctors shifted treatment from older medicines.
Novartis said it would present the result of the trial at the European Society of Cardiology in September, and discuss next steps with clinical experts and regulators.
The company's shares shed 1.4% to 91.20 Swiss francs ($91.90) in early trading in Zurich following the news.
Analyst Michael Nawrath at Zuercher Kantonalbank said the likelihood of a positive outcome in the study had been low, since efforts to tackle this form of heart failure have yet to bear results. There are currently no approved treatments for preserved ejection fraction heart failure.
"The milder the disease the higher the hurdle," he said. "It would have been very good for the momentum of Novartis, whose shares would have passed the 100 franc per share mark, on a positive outcome.
"Despite the relatively low expectations, we are talking about a negative but not sustained price reaction."
($1 = 0.9924 Swiss francs)
(Reporting by John Revill; Editing by Kirsten Donovan)