FDA officials gave expedited approval to the first-of-a-kind pill, called daraxonrasib, which blocks a mutated protein that fuels tumor growth in more than 90% of pancreatic cancer cases. It’s an approach that previously eluded drugmakers for decades.

The daily pills will be sold by Revolution Medicines under the brand name Rasonque. A one-month supply would cost approximately $39,800, the company announced.

Patients taking the drug nearly doubled their survival time, with fewer severe side effects, in a study that randomly assigned them to receive the experimental treatment or more chemotherapy. The company-funded study enrolled 500 patients whose metastatic, or spreading, cancer had quit responding to prior treatment.