A new cancer drug being developed by Singapore researchers could, in the coming years, throw a lifeline to hundreds of people here each year suffering from a range of cancers.

It is being tested on patients here and, if successful, ETC-159, as the compound is now called, could emerge as the Republic's first cancer blockbuster.

Developed by the Experimental Therapeutics Centre (ETC) and Drug Discovery and Development (D3) unit of the Agency for Science, Technology and Research (A*Star), and Duke-NUS Graduate Medical School, the compound homes in on proteins that cause excessive cell growth when they go rogue, leading to cancers.

These particular cancer-causing mutations occur in up to 5 per cent of cancer cases in Singapore, and are caused by hyperactivity of a protein called Wnt, said Professor David Virshup, director of the Cancer and Stem Cell Biology programme at Duke-NUS, and one of the leaders of the effort.

Wnt, when hyperactive, instructs cancer cells to keep proliferating, tells them not to transform into mature cells, or both.

"One way you get cancer is when the cells grow too fast and another way is when they forget to grow up," Prof Virshup explained.

The team believes the drug is able to prevent cancers from growing by blocking the Wnt signal.

The drug discovery and development process started five years ago and trials have been completed successfully on mice.

ETC-159 is now being tested on patients at the National Cancer Centre Singapore and the National University Hospital. Clinical trials will be extended to the United States later.

Professor Alex Matter, chief executive of ETC and D3, said an advantage the drug candidate has over chemotherapy is that it is more specific in targeting cancer cells, which means it leaves normal cells relatively untouched.

Prof Virshup said: "If the cancer is fuelled by mutations that makes it depend on Wnt, this new drug will cut off its fuel."

But Prof Matter noted that one potential side effect of ETC-159 is bone loss, which is something the team will be keeping a close watch on during clinical trials.

Phase 1 of clinical trials will be conducted in two stages: to fine-tune the right dosage to make it safe for humans, and to test its effectiveness on patients with mutations. This applies to around 600 of the 13,000 people who get cancer each year.

It is the first time a publicly funded drug candidate, discovered and developed in Singapore, is being tested on people here.

The little pill could also represent something bigger: that the billions of dollars poured into biomedical research are paying off.

Dr Benjamin Seet, executive director of A*Star's Biomedical Research Council, said the breakthrough, which closely follows local company MerLion Pharmaceu-ticals' recent success in obtaining US Food and Drug Administration approval for one of its drugs, marks an inflection point in the country's biomedical sciences initiative.

"I am confident that we will see more locally developed drugs in the pipeline being tested and implemented," he said.

Indeed, two local groups announced breakthroughs yesterday that could pave the way for treatments for dengue and Parkinson's disease.

But it could still be some years before ETC-159 is available to patients as drug development - from conception to market - typically takes 10 to 15 years.

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