A lung-cancer treatment and medication to help patients with high cholesterol are being added to the Pharmaceutical Benefits Scheme, saving Australians thousands of dollars.

"These listings with help the thousands of Australians and their families fighting lung cancer and the devastating impact of heart disease," Health Minister Greg Hunt said on Sunday.

The drugs will be on the PBS as of next month.

Listing immunotherapy drug Keytruda on the PBS will give more than 1000 Australians with untreated lung cancer access to the discounted medication.

The pharmaceutical company behind the drug, MSD Australia, says the listing if of the "utmost importance" to patients with advanced lung cancer.

Repatha, a drug used to treat high cholesterol that works differently from statin treatment, is also being listed on the PBS.

This will help about 77,000 Australians with a genetically inherited risk of high cholesterol access the drug, which helps to lower "bad cholesterol" in the blood.

Royal Perth Hospital's Gerald Watts says about one in every 250 Australians have the illness, which causes high cholesterol despite a person's age, physical activity and diet.