The Food and Drug Administration approved on Wednesday a new drug for advanced pancreatic cancer, ushering in a new era of treatment for a disease that has long been considered one of the most hopeless in medicine. The drug, taken as two pills a day, is the first of its type and has electrified cancer specialists and patients. It is not a cure, but it is the first treatment to substantially extend the lives of patients with pancreatic cancer.

The drug, daraxonrasib, is made by Revolution Medicines and will be sold under the brand name Rasonque. It was approved for patients who have metastatic pancreatic cancer and have already tried chemotherapy. In a key clinical trial, participants who got daraxonrasib lived for a median of over 13 months, compared with less than seven months for those who got chemotherapy. Some patients who have gotten the drug through clinical trials have lived for years.

“We’ve never seen a benefit like this,” said Dr. Anna Berkenblit, the chief scientific and medical officer at the Pancreatic Cancer Action Network. Revolution Medicines did not immediately announce how much it planned to charge for the drug. Wall Street analysts have said they expect the drug’s sticker price to be several hundreds of thousands of dollars a year. Since May, more than 2,000 patients have received free, early access to the drug through an expanded access program.

Nearly all pancreatic cancers are fed by a mutated cellular protein called KRAS. Daraxonrasib uses a novel approach that glues molecules together to grab and shut down KRAS. The researcher who led the key study, Dr. Brian Wolpin of the Dana-Farber Cancer Institute in Boston, said he was stunned by the trial results. “I have not seen anything like that before in trials we have run in pancreatic cancer,” he said.