Clinical trial for new cancer drug Deflexifol shows fewer side effects

Collaborators: Illawarra oncologist Professor Philip Clingan and University of Wollongong scientist Marie Ranson. Picture: PAUL JONES
Collaborators: Illawarra oncologist Professor Philip Clingan and University of Wollongong scientist Marie Ranson. Picture: PAUL JONES

A new cancer drug developed at the University of Wollongong is offering renewed hope to Illawarra patients who have failed all other treatment options.

So far seven cancer patients have embarked on the clinical trial of the chemotherapy drug, Deflexifol, at Southern Medical Day Care Centre in Wollongong.

Renowned Illawarra oncologist Professor Philip Clingan is overseeing the human trial, after the drug showed remarkable results in animal trials.

It's still early days for the human trial, which started in December, but patients are already reporting far fewer side effects while two of the patients have seen a halt in the progression of the disease.

That was significant, Professor Clingan said, as the 12-month trial was available only to patients with metastatic cancer (cancer that has spread) that had failed to respond to other available treatment options.

"We are about a third of the way through the phase one clinical trial which is testing the drug in a small group of patients for the first time to identify any side effects and to work out the best dosage," Professor Clingan said.

"So far there have been no complications - it's being very well tolerated by patients and there's been none of the usual side effects like nausea, diarrhoea and mouth ulcers. Meanwhile two patients have had stabilisation of disease."

The next phase of the trial will look at how to make the drug more effective in treating metastatic cancers - including colorectal, gastrointestinal, breast and pancreatic cancers.

It's been a long project for Professor Clingan who initially approached Wollongong chemist John Bremner a decade ago to develop a chemo drug with fewer side effects for his patients.

Emeritus Professor Bremner, of the University of Wollongong's School of Chemistry, was able to adapt an existing drug called 5-Fluorouracil, or 5-FU, which is not well tolerated by many patients. That drug only works effectively in conjunction with an "activator" called leucovorin but this has to be injected separately as it does not mix well with 5-FU.

Further the high alkalinity of the 5-FU means it has to be administered as an infusion over 24 to 48 hours, necessitating a portable catheter system.

"5-FU is one of the most widely used anti-cancer drugs in the world and the most common side effects are nausea, diarrhoea and mouth ulcers," Professor Clingan said.

"Because of the way it is administered there are also associated problems like phlebitis at the injection site and blockage of the catheter. So several years ago I went to see [Professor] Bremner who was able for the first time to use a carrier model to put both drugs together in a new compound.

"This has the same pH level as blood so can be injected in one go rather than infused for long periods of time."

Once the new drug was patented, Professor Marie Ranson of the Illawarra Health and Medical Research Institute was brought in to conduct pre-clinical trials.

"Many patients have to stop the original regime because of the formulation and complications associated with its administration," Professor Ranson said.

"By mixing the two drugs together using a carrier called cyclodextrin it has enabled us to make an all-in-one solution which has been very well tolerated and very effective in animal trials. In those trials, none of the animals showed any signs of vein irritation, they showed reduced signs of toxicity and all were able to finish a treatment cycle."

Professor Ranson said as a cancer researcher it was rewarding to see the drug make it from the laboratory bench into a human trial.

lwachsmuth@fairfaxmedia.com.au