Mr Daly's 10-year-old daughter Kate was diagnosed with cystic fibrosis at birth and although she is ineligible for a breakthrough treatment known as Kalydeco because of her particular gene mutation, he has joined the fight to have the drug listed on the Pharmaceutical Benefits Scheme.

"We're one of the only developed nations that doesn't have it as a subsidised drug," he said.

"It's vital that those children get that drug, not just for the compassionate reasons but for the long term benefit of cystic fibrosis. It's critical that people are given access to it, not only to save them now but for what it can do for research going forward."

Mr Daly joined other parents of children with cystic fibrosis and CF sufferers at Parliament House on 65 Roses Day on Wednesday to urge the federal government and Health Minister Peter Dutton to list Kalydeco on the PBS.

About 200 Australians with a specific form of cystic fibrosis would benefit from the treatment if it was subsidised through the PBS.

Kalydeco is the first medicine which treats the underlying cause of cystic fibrosis and works by "turning off" the genetic defect which causes CF and the build-up of thick mucus in the lungs and digestive system. For people with a specific gene mutation known as G551D, this means dramatically improved lung function and a reduction in respiratory and gastrointestinal complications.

Mr Dutton attended Wednesday's event, where he spoke to parents and heard their personal stories and met people whose lives have been transformed by Kalydeco.

"The government is not deaf, by any stretch of the imagination, to the cries of families around the country and we want to provide whatever support we can and we want to provide that as quickly as possible and negotiations with the company in relation to this medicine have been ongoing and we're continuing, as late as last night, and that's the situation as best I can explain it to you," he told the crowd.

"I hope we can provide for a brighter future for children who are most deserving but for their families as well."

Cystic Fibrosis Australia president Mitch Messer said Kalydeco was the first drug which treated the underlying cause of the condition.

"We have a group of about 200 Australians whose lives would be changed forever by having access to that medicine - unfortunately that drug costs about $350,000 a year," he said.

"The cystic fibrosis population can't afford to pay that ... every two years, it'd be the equivalent of a new house. We're now looking to have that drug listed on the Pharmaceutical Benefits Scheme.

"We understand government is in a tight situation, we also understand the PBS costs $9 billion a year to the Australian taxpayer but we need the government to understand, and the department to understand, a parent's anguish for their child's long-term health and long-term outcomes.

"We don't want to be talking about people with cystic fibrosis surviving into their 30s, we want to be talking about people with cystic fibrosis having the same life opportunities as everybody else. Our vision for cystic fibrosis in Australia is life unaffected by cystic fibrosis and this drug will help us take one step closer to that."

A spokeswoman from Kalydeco's manufacturer Vertex said the company was working with the Health Department.

"There's a very formal process in Australia so we've really been following that process to reach a positive conclusion as quickly as possible to get the medicine to patients," she said.

"At the end of the April, the Pharmaceutical Benefits Advisory Committee recommended Kalydeco for a second time so the decision is now with the Department of Health."

The spokeswoman said the PBAC had recommended strict eligibility criteria for the drug, which Vertex did not agree to.

"These conditions that they've recommended would disqualify effectively half the patients currently eligible for Kalydeco," she said.

"We believe all the people with that gene mutation, who are aged six and older, should be able to get the medicine, that there shouldn't be this criteria and that's the agreement we've reached with countries around the world ... and that's what we've submitted back to the government as an alternative proposal."

As a parent of a child with cystic fibrosis, Mr Daly acutely understands the importance of families having access to the treatment if it can help them.

"I would hate to see other parents have their children pass away because they couldn't afford to buy the drug for them. It is a very expensive drug, but it is a life-saving drug," he said.