The drug, Ceritinib, made by Novartis, was already approved in the United States but was undergoing further trials.
Mr Brosnan grabbed the opportunity to join the Auckland arm of the trial. At first, he was in its chemotherapy group for nine months and this medicine controlled his tumours without shrinking them. When they began growing he was switched, last August, to the trial medicine, also called LDK378.
The pills have made a remarkable improvement: the tumours in his lung and liver have shrunk and the smaller ones -- in his brain and chest -- have disappeared.
"I feel good. I don't have as much energy as I did and I do get fatigued, but I was able to trim the hedges and trees," says Mr Brosnan.
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He suffered some side effects, the worst of which was losing 10kg from his 61kg frame, but this was managed by stopping the pills temporarily, then resuming at a lower dose and consuming a high-energy diet.
A lifetime non-smoker, Mr Brosnan has wondered what may have contributed to him developing lung cancer. He considers the facts that he grew up in a home with a father who smoked, and worked as a railway fitter and ship's engineer, jobs which exposed him to steam-engine smoke and the widespread use of asbestos fibres to insulate boilers, exhaust pipes and other machinery.
"We used to wrap the locomotives with raw asbestos, big 100-tonne trains and above them there was just a cloud of asbestos," he recalls of his time at the Hillside railway workshops in Dunedin from the late 1950s.
One of his specialists, Associate Professor Mark McKeage, of the cancer centre, University of Auckland and Auckland City Hospital, hailed Mr Brosnan and other patients for joining clinical trials and taking their chances with new medicines.
"He's a hero really in that they go on trials despite all the uncertainty associated with it and for altruistic reasons -- even if the trial doesn't work, the knowledge gained will help other people."
Mr Brosnan reversed the compliment to his doctors and health support workers: "It's those guys are the heroes. They save your bacon."
The Auckland Cancer Society Research Centre, based at the University of Auckland, is a scientific unit devoted to discovering and developing new drugs to treat cancer. It also runs clinical trials of its own and other organisations' drugs. A fifth of its funding comes from the Auckland/Northland division of the Cancer Society, a charity.
The Conquering Cancer open day will be held on Saturday, 9.30am to 3pm, at the Auckland Cancer Society Research Centre. Entry is free. More than a dozen short talks will be offered that give a glimpse into the work of the centre's researchers. On Thursday April 14 at 6.30pm, Canadian cancer researcher Professor Ian Tannock, of the University of Toronto, will give a free public lecture at Auckland University.
People wishing to donate to the Cancer Society can visit cancernz.org.nz or donate or call (09) 308 0172