Novartis' serelaxin fails to meet goals of late-stage acute heart failure study

Novartis announced Wednesday that a Phase III study of the experimental drug serelaxin in patients with acute heart failure (AHF) failed to meet its primary endpoints of reduction in cardiovascular death through day 180 or reduced worsening heart failure through day five when added to standard therapy. Chief medical officer Vas Narasimhan said the company will "evaluate next steps for the overall programme."

The RELAX-AHF-2 trial, which started in October 2013, included 6600 patients hospitalised for AHF and was designed to evaluate the efficacy, safety and tolerability of serelaxin, also known as RLX030, when added to standard of care. Narasimhan said Novartis "will continue to further analyse the data to better understand and learn from these results."

Serelaxin, a relaxin receptor agonist, is a recombinant form of the naturally-occurring human relaxin-2 hormone, with analysts estimating that the drug could have generated sales of $359 million by 2020. However, serelaxin was rejected by the FDA and European regulators in 2014, with both asking for further evidence of the therapy's ability to prevent heart disease from worsening as part of a treatment programme.

Commenting on the latest news, analysts suggested that the failure of serelaxin will increase pressure on Novartis to boost sales of its heart failure treatment Entresto (sacubitril/valsartan), which have so far fallen below expectations. Sales of Entresto, which was approved in the US and Europe in 2015, reached $170 million last year, missing the company's target of $200 million. "The failure of serelaxin will refocus the importance of Entresto to meet consensus long-term sales expectations as well as the importance for management to bolster its pipeline," noted Deutsche Bank analyst Tim Race.