Abortion pill RU486 and three cancer drugs have been subsidised, with the Federal Government adding them to the Pharmaceutical Benefits Scheme (PBS).

Health Minister Tanya Plibersek has announced 17 new or amended PBS listing that will cost $1 billion to subsidise over the next four years and make them available at a cheaper price for consumers from August.

Ms Plibersek says a number of the cancer drugs cost more than $100,000 and will be able to be purchased for under $40.

Women have paid up to $800 for the RU486 pill, but Ms Plibersek says from August it will cost less than $37.

"It doesn't change any legal position around abortion and it doesn't change the number of women who are likely to terminate a pregnancy," she said.

Ms Plibersek says about 22,000 women have already used RU486 through some clinics.

"What the provision of these medicines does is give women slightly more choice and more options," she said.

"I think that is a good thing in the situation where women are faced with one of the most difficult decisions that they will ever make."

Treatments for skin, breast and prostate cancer have also been added, including Ipilimumab and Abiraterone.

The subsidy for breast cancer treatment Vinorelbine has also been extended.

"The exciting thing about these new treatments is that they will extend the life of patients with melanoma, prostate cancer and breast cancer," Ms Plibersek said.

"If we didn't subsidise they would be out of the reach of most Australians."

Tilly Ryan from Melanoma Patients Australia has praised the move.

"Our members will no longer have to look at selling their homes to access treatment," he said.

Cancer survivor Christine Bleigie says Ipilimumab costs more than $110,000 a year and was not affordable to most suffers of malignant melanoma.

"We have people in our melanoma patient support groups that are just waiting on this drug to be on the PBS listing because they just can't afford it," she said.

"They are fourth stage melanoma people and so this to them is just the best days in their lives."