RPA clinicians discover gene therapy cure for thalassaemia.
In a world first, Royal Prince Alfred Hospital clinicians are among an international team to have found a gene therapy cure for thalassaemia, a common condition where sufferers must undergo regular blood transfusions and treatments for iron-overload for life.
Thalassaemia affects more than 280 million people, with about half a million people worldwide and up to 1000 Australians suffering from the severe form. Those affected produce fewer red blood cells and less haemoglobin, which means less oxygen is delivered around the body.
In a ground-breaking clinical trial, published in The New England Journal of Medicine, 22 participants with severe beta thalassaemia across three sites (United States, Thailand and Australia) had their own blood stem cells extracted.
Scientists in the United States then inserted a healthy copy of the affected gene into the stem cells that were maintained outside the body. Back home, the Australian patients were given chemotherapy prior to receiving their own genetically modified cells by intravenous infusion.
Following the trial, 15 of the participants no longer needed blood transfusions. The remaining seven still received transfusions but only needed one quarter of the volume compared to their previous requirements.
Trial lead and head of Cell and Molecular Therapies at RPA, Professor John Rasko AO, said the results build on many recent breakthroughs in gene therapy to treat immune deficiencies, blindness, haemophilia and leukaemia.
“This is an absolute thrill for me; a watermark moment in my life,” Professor Rasko said. “To be able to offer patients a cure now or in the future is a dream come true for me and the culmination of more than 25 years’ work. It is also a stepping stone for us to focus on more than 4000 other genetic diseases which have no cure or suitable treatment.”
For participant Jack Saenprasert, 38, from Rockdale, the trial has been life-changing.
A chef and father of four, he underwent monthly blood transfusions at RPA for nine years. Since receiving his own gene-modified cells about two and a half years ago, he has not needed a blood transfusion.
“I had to take the day off work every month, plus come in the day before for cross-matching of the blood. It was very difficult with work. Some bosses don’t understand, or don’t want to understand. I tried going without the transfusions but I’d get so tired and yellow, Now, I feel fresh and healthy, and I can take my children to the beach and the park,” he said.
Stacey Wong, 28, from Blacktown, also participated in the trial. She still needs transfusions but requires less units of blood less frequently.
“I think the doctors were a little disappointed that I still need transfusions, but I’m not. The number of times I visit the hospital is incidental because my quality of life has significantly improved. Every day before this trial I would be exhausted, thinking about when I could rest and feeling like I was letting my family and friends down, but now I feel so much better and I’d do it all again in a heartbeat.”
Stacey is now planning her wedding in October and – for the first time – can leave Australia for a month-long holiday without worrying about regular hospital visits.
Bluebird Bio is funding the commercialisation of the gene therapy trial.