Australian researchers say a combination of immunotherapy drugs may help increase life expectancy for patients with advanced melanoma.

Advanced melanoma patients with brain tumours may be able to live longer using a combination of immunotherapy drugs, an Australian trial has shown.

Of 67 people given with the immunotherapy drugs nivolumab and ipilimumab in a Melanoma Institute trial between 2014 and 2017, more than three-quarters remained alive six months after starting treatment.

People typically live for four to five months after being diagnosed with brain metastases - cancer cells that have spread from tumours in other parts of the body - the study's chief investigator Georgina Long says.

The trial also found that two-thirds of the 41 patients who took nivolumab alone remained alive at the six month mark.

"It's a game changer. This is absolutely new information," Prof Long told AAP.

"I have melanoma patients with brain metastases who would not be alive today if they had not participated in this trial."

People diagnosed with this cancer were in the past excluded from clinical trails because their prognosis was so dire, Prof Long said.

Findings from a further 11 people involved in the phase two trial will be released in a few months after they have additional brain scans.

The trial was partially funded by Bristol-Myers Squibb, the company behind the two immunotherapy drugs.