CHICAGO — Revolution Medicines will release full results of its Phase 3 clinical trial for daraxonrasib, a KRAS-targeting pill for pancreatic cancer, at the American Society of Clinical Oncology annual meeting in Chicago. The company developed daraxonrasib as a RAS inhibitor designed to block multiple mutations of the KRAS gene without requiring patients to undergo specific mutation screening.

Daraxonrasib is being evaluated as a second-line treatment for patients who have already undergone standard chemotherapy or other cancer therapies. Initial findings from Phase 1 and 2 trials showed that patients treated with daraxonrasib had a median overall survival of 13.2 months, compared to 6.7 months with standard chemotherapy alone. Among 168 patients with pancreatic ductal adenocarcinoma (PDAC), those with the RAS G12 mutation—the most common KRAS variant in PDAC—had a median overall survival of 13.1 months and 8.5 months of progression-free survival.

More than one third of patients with the RAS G12 mutation experienced an objective response, defined as at least 30% tumor shrinkage on CT scans. However, about 30% of patients also reported severe side effects. Revolution Medicines noted that 90% of patients developed a rash, and approximately half experienced diarrhea or inflammation of the mouth or gastrointestinal tract. Other side effects included nausea, vomiting, and fatigue.

"For that to exceed one year is really extraordinary," said Dr. Emil Lou, professor of medicine at the University of Minnesota Medical School and medical oncologist.

The U.S. Food and Drug Administration granted fast-tracked limited approval for daraxonrasib on April 30, allowing expanded access for eligible patients. However, as of the report date, physicians do not yet have access to the drug despite this authorization. Dr. Elizabeth Jaffee, oncology professor and deputy director of Johns Hopkins' Sidney Kimmel Cancer Center, said, "That just opened up the whole field." She added, "For all the years that I've been treating and developing new therapies for pancreatic cancer, it's still a death sentence." Jaffee said daraxonrasib has "manageable toxicities" compared to chemotherapy. "We're very hopeful that we're going to see even better results when we start this drug earlier," she said. "We've hit on the first component of this pathway. Now we have to figure out combinations. This will be a little bit more complex, obviously. But a lot of work's already being done."