Targeting a new enzyme as a promising treatment for heart attacks and heart failure

Published: 23 September 2024

Dr Nicola Scott will be researching how inhibiting the heart enzyme PDE9 may reduce damage following a heart attack and could also lead to a potential new treatment for heart failure.

Dr Nicola Scott feels like she’s achieved the Holy Grail for pre-clinical researchers in medical science, with recent news that a medication based on a heart enzyme she’s been studying will start clinical trials in patients in New Zealand soon.

“It’s like winning the lottery,” she exclaims, “to see that our research has contributed to this and we’ll now be part of multinational clinical trials to test this treatment.” 

The Heart Foundation recognises the research significance and has awarded Nicola a Project Grant and Senior Fellowship to further investigate the clinical potential of the heart-specific enzyme, called PDE9 (phosphodiesterase-9).

“This promising discovery highlights the importance of supporting research from bench to bedside with hopefully a tangible benefit at the end if the clinical trials go well,” says Dr Gerry Devlin, Heart Foundation Medical Director.

New treatment for heart damage and heart failure

At the Christchurch Heart Institute (University of Otago, Christchurch), Nicola will be researching a new method of enhancing the beneficial actions of heart hormones, called natriuretic peptides, by inhibiting PDE9. The heart hormones have a wide range of favourable effects on the cardiovascular system, such as controlling blood pressure and fluid volumes.

Inhibiting PDE9 could help reduce heart damage following a heart attack and may also lead to a potential new treatment for heart failure, a condition where the heart is unable to pump blood as effectively as it should.

“It’s incredible to think that this groundbreaking research is something that my friends and family might benefit from in the future,” says Nicola. 

Following a heart attack, the heart can undergo changes in structure which result in decreased pumping ability. Inhibition of the PDE9 enzyme may be able to minimise these harmful changes and reduce the risk of heart failure.

Nicola will also investigate combining PDE9 inhibition with ACE inhibition, and explore whether this offers greater benefit for treating heart failure than either treatment alone. 

ACE inhibitors (angiotensin-converting enzyme inhibitors) are the current frontline medication for treating heart failure and are taken by nearly half a million New Zealanders, so it’s important to examine the safety and efficacy when combined with PDE9 inhibition.

Back in 2017, a Heart Foundation grant funded initial research into the potential of inhibiting PDE9, and Nicola is very grateful for their support. “Credit to the Heart Foundation for supporting the whole spectrum of research, from the beginning of the research process through to putting it into clinical practice.”