Australian medical researchers have made a breakthrough in the treatment of a chronic form of leukaemia they hope will improve the quality of life for many people living with the disease.
A Phase 2 clinical trial, published in journal Annals of Internal Medicine, has shown treatment-free remission was achievable in patients with chronic myeloid leukaemia (CML) who were treated with a "potent" new drug called nilotinib.
The trial's lead investigator, Professor Tim Hughes of the South Australian Health and Medical Research Institute, says the results will have an impact on the way doctors treat the disease.
Drugs known as tyrosine kinase inhibitors (TKIs), which target the enzyme causing the leukaemia, have dramatically improved outcomes for patients with CML, however the majority (80 per cent) must remain on medication for life even when clinically in remission, says Professor Hughes.
This causes many side-effects and impacts greatly on their health.
The most common side-effects include severe fatigue, severe muscle pain and cramps, and gastrointestinal problems such as diarrhoea and vomiting.
"About a quarter of these patients tells us the side-effect are in some cases unbearable, another 25 per cent say that the side effects are significant enough to impair their quality of life," said Professor Hughes, who works as a consultant haematologist at Royal Adelaide Hospital.
"That's half the patients who are really struggling to take their drug and have a significant impairment in their quality of life, so to be able to come off therapy is a huge step for those patients," he told AAP.
For the trial, researchers studied 163 patients who had achieved a sustained deep molecular response (DMR) after switching from drug imatinib to the newer, more potent TKI nilotinib.
Deep molecular response is the the goal of therapy and often predicts if a patient can achieve treatment-free remission.
Of the trial participants to achieve DMR, 52 per cent were able to maintain treatment-free remission at two years and 38 per cent at five years, according to the results.
"This trial was specifically designed to test whether the responses we saw with nilotinib could translate into more patients achieving treatment-free remission, and we've now shown that's in fact the case," said Prof Hughes.
"We are no longer talking about just 20 per cent who can achieve this optimal result with the kinase inhibitor therapy, with the availability with the newer drugs we may be able to increase that to 40 or 50 per cent of patients, so that's a very major step forward and very good news with patients with chronic myeloid leukaemia," said Prof Hughes.
Of those patients who can benefit most from this new therapy option are younger adults still wanting to start a family, said the medical expert.
