The U.S. FDA has approved a brand new type of targeted drug for the treatment of pancreatic cancer, marking a breakthrough in the treatment of the disease.

Over the previous few decades, numerous treatment advances have meant that people diagnosed with most types of cancer have a significantly improved chance of survival. But it has been very difficult to make substantial improvements for pancreatic cancer, which is often diagnosed at late stages, spreads to other parts of the body and is resistant to many conventional treatments.

On Wednesday, the FDA approved daraxonrasib, marketed as Rasonque by Revolution Medicines, for adults with the most common type of pancreatic cancer, pancreatic ductal adenocarcinoma (PDAC), which has spread to other parts of the body and where other treatment approaches have failed.

Daraxonrasib is the first targeted therapy specifically approved for this form of pancreatic cancer and inhibits a protein called RAS, a molecular switch which can get stuck “on,” driving growth of cancer cells. Daraxonrasib blocks this switch and inhibits cancer cell growth. More than 90% of patients with PDAC have mutations that switch RAS on, meaning physicians are hopeful that the drug will be effective for many patients with the disease.

The FDA’s decision was supported by impressive clinical trial results presented at the annual American Society of Clinical Oncology meeting showing a substantial survival advantage for patients treated with daraxonrasib compared with chemotherapy. In the pivotal study, patients receiving the drug had a median overall survival of 13.2 months, compared with 6.7 months among those receiving chemotherapy. As the results were presented, over 9,000 conference attendees gave a standing ovation, with many declaring it a substantial breakthrough. The data was simultaneously published in the New England Journal of Medicine .

“These results are landscape-changing for metastatic pancreatic cancer patients with a KRAS mutation. We are seeing unprecedented survival and efficacy in second-line treatment with an expected safety profile,” said Rachna Shroff, MD, MS, Chief of the Division of Hematology/Oncology at the University of Arizona Cancer Center in an ASCO press release at the time.

For people with metastatic PDAC, treatment has previously largely relied on combination chemotherapy regimens. These treatments can extend survival but also regularly cause substantial toxicity, including fatigue, nausea and other side effects that can be particularly challenging for patients, dramatically affecting their quality of life without significant chance of long-term survival. In the trial, which compared daraxonrasib with chemotherapy, 11.2% of the patients on chemotherapy had to stop treatment because side effects were so severe, compared to just 1.2% of people taking daraxonrasib. These findings also suggest that the drug may be gentler on patients than conventional chemotherapy.

“To date in my career, I have not seen this level of benefit from any single anti-cancer drug in this disease,” said Eileen O’Reilly, MD, medical oncologist and one of the leaders of the trial from Memorial Sloan Kettering Cancer Center (MSKCC) in New York in a press release . “It’s very encouraging that we are seeing these kinds of results for people with pancreas cancer on a large scale.”

Even more encouraging is that RAS mutations are present in several different types of cancer, giving hope that the drug might also be effective in other cancer types. Several clinical trials are already underway investigating this.