'This is the future': ACT trials gene-editing to treat heart patient

The 82-year-old's cardiologist Dr Walter Abhayaratna is the director of clinical trials at Canberra Hospital and brought the "Magnitude" trial to the ACT.

He said the hospital served a wider population of more than 1 million and wanted patients in the region to have access to this "one-off" treatment.

"I'm very proud that we've got it here. It is cutting-edge technology. This is the future," Dr Abhayaratna said.

He said the trial was aimed at Mr Jelf's rare heart condition called cardiac amyloidosis, a disease caused by gene mutation.

Mr Jelfs is from Tuross Head village, two-and-a-half hours from the ACT, but lived in Canberra for 28 years. He was the manager of a medical supply company, Capital Medical Supplies, before retiring to the coast.

He has been surfing since he was "knee-high to a grasshopper" and only took a break in August last year when he began feeling breathless.

"I was born and bred in Sydney and I was in Bondi Surf Club, so surfing and saltwater is in my veins," he said.

When Dr Abhayaratna told him about the Magnitude trial Mr Jelfs said it was a "no-brainer" to be part of it.

He's hoping to be one of the heart patients who has been given the actual treatment in this placebo trial so he can get back to surfing.

"I've got a lot of hope," Mr Jelfs said. "If I have been fortunate enough to get the gene therapy ... it's not going to cure me but it will certainly save my life."

Due to its hereditary nature, Mr Jelf's younger brother and son were believed to have the same condition. Unfortunately, his brother died shortly after receiving a heart transplant and his son died at just 14.

In cardiac amyloidosis a protein (amyloid) is abnormally produced and dumped into tissues, making the heart stiff and unable to fill up with blood, resulting in congestive heart failure.

Symptoms include becoming very short of breath, having tense bellies from excess fluid, swelling in the legs and not being able to lie down.

"Routine medications for heart failure for these particular patients are very poorly tolerated, blood pressure becomes very low, they become very tired and dizzy," Dr Abhayaratna said.

"This form of treatment that we've got in the Magnitude study is groundbreaking to the point where ... we're not just treating the symptoms, we're going back to the abnormal protein."

There are 20 amyloid proteins associated with amyloidosis and one of them - transthyretin - is produced by genes.

In the clinical trial, patients are given a single drug infusion to identify the gene, "cut" out the part producing transthyretin and put the gene back together.

"The rest of the chain of genes is still working, but no more transthyretin production," Dr Abhayaratna said.

"Over time, the body will slowly clear that protein so the heart can actually start to repair."

This type of gene-editing is also called CRISPR-Cas therapy for monogenic (caused by a single gene) diseases. Bacteria and viruses use CRISPR-Cas as a natural immune defence.

We've taken the technology and mimicked it, we've learned from lesser developed organisms to do something that's very developed in our bodies," Dr Abhayaratna said.

Three patients in Australia are part of the Magnitude trial. Two have been given the real drug infusion while one has been given a placebo. The treatment has been developed by American company Intellia Therapeutics.

In phase three of the drug trial to record effectiveness, Mr Jelfs receives an infusion as well as new medication from time to time. He will be part of the study for 18 months.

"Even when on placebo we find that a lot of patients do better than the usual because they're actually getting better care," said Dr Abhayaratna, who has been closely monitoring Mr Jelfs every week.

"The comparison between those who got the real drug and the placebo to see what the benefits are. And that's the way we do a randomized clinical trial."

Mr Jelfs added: "He gives me confidence in what's going on. I have a lot of time for that man."

Patients with this disease are often diagnosed later in life and they are usually men in their 70s or 80s. A delayed diagnosis reportedly causes high mortality among these patients.

Dr Abhayaratna said some countries reported one-sixth of the patients with the most common type of heart failure (with preserved ejection fraction) have cardiac amyloidosis.

"It's uncommon, but it's more common than it's being reported," the former president of the ACT Australian Medical Association said.

In February, an article in the Lancet medical journal said heart failure with preserved ejection fraction (HFpEF) was being increasingly recognised and diagnosed. It stated an ageing population and a rise in co-existing conditions, like obesity and diabetes, were driving this trend.