Synthetic virus may cure heart failure

Human trials of a pioneering gene therapy involving injections of a synthetic virus that can boost heartbeat are set to kick off in Britain within weeks.

Two new studies hope to offer hope to those with heart failure struggling to lead a normal life.

"Our goal is to fight back against heart failure by targeting and reversing some of the critical molecular changes arising in the heart when it fails," said Alexander Lyon, a consultant cardiologist at the Royal Brompton Hospital in London and lead investigator for the two studies.

The trials, involving about 250 patients, will look at whether the pioneering treatment is safe, reduces emergency admissions and improves quality and length of life.

The first trial will be carried out at the Royal Brompton in London and the Golden Jubilee National Hospital in Glasgow.

The patients will be part of a group of 200 from around the world who will have the virus injected via a cardiac catheter inserted through a vein in the leg.

A second trial at the Harefield and Papworth hospitals will be based entirely within the UK and involve 24 patients with chronic heart failure who are already fitted with an "artificial heart" known as a left ventricular assist device, which helps to pump blood around the body.

The aim in both trials is to inject additional copies of a healthy gene, known to be responsible for a key protein involved in regulating the rhythmic contraction of the heart muscle.

It is hoped that the extra genes will remain active within a patient's heart for many months or even years.

Scientists warned that it will still be several years before the technique can be made widely available.

"It's been a painstaking, 20-year process to find the right gene and make a treatment that works, but we're thrilled to be working with cardiologists to set up human trials that could help people living with heart failure," said Prof Sian Harding of Imperial College London.

The trials are based on years of research in the lab and recent safety trials in patients in the US.

So far, 37 people in the world have had gene therapy for heart failure, but until now, the experiments have aimed only to investigate its safety.

The second trial is funded by the British Heart Foundation, which has also supported 20 years of research.

The treatment aims to increase the expression in heart muscle of a protein produced by the SERCA gene, which signals a flow of calcium to the muscle cells, which then contract.

More calcium means a stronger heartbeat.