Not only was he accepted into the first clinical trial of a drug that had the potential to cure his melanoma, he could also afford the cost of both flying to the United States to participate, and the drug itself – a whopping $120,000 a year.

What's more, the drug, which carries about a 40 per cent cure rate, saved his life – he was last month declared cancer-free.

The millionaire chairman of the Australian Grand Prix Corporation, last year successfully helped push to get the drug, Keytruda, listed on the government's Pharmaceutical Benefits Scheme so that others could share in its benefits.

"I tried everything else except this new drug on trial..." Mr Walker said. "I remain the luckiest guy in the world to get it and have it work. It doesn't work on everyone and I just wanted to share my luck around."

Many more Australians are likely to face the decision of whether to enrol in clinical trials or obtain such drugs privately for a discount or free, with an Australian Medical Journal article revealing on Monday that hundreds more cancer drugs are expected to enter the market over the next five years.

"Of the cancer medicines being developed, 91 per cent will be targeted therapies, which is likely to make these medicines more expensive," the article, by Narcyz Ghinea and Dr Wendy Lipworth, from the University of Sydney's Centre for Values, Ethics and the Law in Medicine, said.

Given the launch price of cancer medicines grew 10 per cent a year over almost 20 years, they said that the federal government would come under greater pressure to subsidise the drugs.

It was important decision-makers "separate the real value of cancer medicines from the hype that often surrounds them", they said. The authors suggested using a tool developed by the European Society for Medical Oncology "that ranks the "clinically meaningful benefit" that can be expected from new cancer treatments."

They argue that the negotiations between the Pharmaceutical Benefits Advisory Committee – which balances the drug's safety against its cost-effectiveness – and drug companies should become more transparent.

While acknowledging companies did not want to reveal their commercial interests, they said that "without greater openness about how funding decisions are made, and how medicine prices are linked to underlying research and development, manufacturing and operational costs, we will remain unable to optimise the utilisation of our health resources in a way that works for both society and the pharmaceutical industry".

A spokeswoman for the Department of Health said the committee was consulting on changes to make its assessments more transparent, including how to consider patients' experiences on new medicines. She said it took on "rigorous clinical and cost effectiveness assessments" for all new medicines before it.

"This ensures that there is independent and fair assessment of the value of treatments to patients' health, and consideration of the longer term impact on the health system through cost effectiveness assessment. The government is also making savings ... to ensure that innovative new medicines that are assessed as clinically and cost effective can be funded in future, and the PBS remains sustainable."

Health Minister Sussan Ley on Sunday announced that a significant number of PBS-listed prescription drugs would become up to $20 or 60 per cent cheaper. This included drugs for cholesterol and high blood pressure.

Mr Walker said he thought Australia was doing more than other countries to approve cancer drugs domestically. He said Keytruda had cost millions of dollars over about a decade to develop "and if drug companies can get a premium on their discovery, they're entitled to it".