Ibrutinib, known as Imbruvica, will cost patients $38.80 a script - or $6.30 for concessional patients - once it is listed on the Pharmaceutical Benefits Scheme from December 1.

The drug will be available to all eligible patients with relapsed or refractory chronic lymphocytic leukaemia (CLL) or small lymphocytic lymphoma (SLL).

Prime Minister Malcolm Turnbull will announce the listing on Monday, saying the drug - considered significantly more effective than many of the treatments already available through the PBS - will change lives.

"This new medicine provides an important new treatment option for Australian patients and now, thanks to my government's commitment to the PBS, is within reach for hundreds of Australian families," Mr Turnbull said.

Around 1000 Australians are expected to benefit from the drug every year.

Retired Melbourne property developer Jim Coomes, 75, was given 18 months to live when he was first diagnosed with CLL. That was four years ago.

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Like hundreds of people with CLL he did not respond to regular chemotherapy. The second treatment he tried came with side effects so severe it led to a heart attack.

Things were looking grim until he was given compassionate access to a clinical trial of Imbruvica.

"It's just been brilliant. It's given me my life back again. I can do all the things I want to do. I buy green bananas again," he told Fairfax Media with a laugh. "But seriously, I was at the point where I had stopped buying new clothes because I didn't think I'd be around to wear them."

With only minor side effects, Imbruvica allows Mr Coomes to "grasp life with both hands". While he's not officially in remission, he feels so good he's even started writing a historical novel set in the Victorian goldfields - and hopes he'll be around to see it through to its conclusion.

Sydney man Robert Domone, 68, was diagnosed with CLL in 2011. His lymph nodes had swollen to the size of grapefruits and the prognosis was not good - until he too got trial access to Imbruvica.

"The outlook was for two to three years of survival and I would have been in and out of hospital with infections. And to get rid of the swelling I probably would have had radiation. It would have been a very uncomfortably existence and I don't expect I'd still be here," he said.

"I'm here because of Imbruvica."

Not just here, but in remission and physically active. Mr Domone bushwalks, does yoga and helps teach disabled children to sail through charity Sailability.

The Coalition has added about $7.5 billion worth of medicines to the PBS since coming to government in 2013, including about 60 new cancer drugs.

Health Minister Greg Hunt said: "The Turnbull government is guaranteeing Medicare and we're continuing to make medicines available and affordable for Australians who need them."

Leukaemia experts welcomed the government's move.

Professor Stephen Mulligan from Sydney's Royal North Shore Hospital called it a "milestone that would be welcomed by patients and their families". Associate Professor Constantine Tam from the Victorian Comprehensive Cancer Centre said he was "delighted" the drug would finally be affordable.

CLL and SLL are types of cancer that affect white blood cells, which are an important part of the immune system and help protect our bodies against infection and disease.

In people with CLL and SLL, the white cells become malignant and spread uncontrollably. This can make people more susceptible to anaemia, recurrent infections, bruising and bleeding. The diseases are most commonly diagnosed in people over 60 and affects more men than women.

Ibrutinib works by blocking the signals that tell the white cells to multiply and spread uncontrollably.