A drug in development for a protein target once thought unreachable by pharmaceutical means has new data showing its potential efficacy in lung cancer.
Thousand Oaks, California-based Amgen announced data from the Phase I/II study of AMG 510 at the World Conference on Lung Cancer, underway in Barcelona, Spain. The drug targets KRAS G12C, a protein that is a known genetic driver of many solid tumor cancers, but was long regarded as “undruggable.” Amgen announced the oral presentation Sunday.
Data presented came from the Phase I portion of the study. They showed that among 13 patients receiving the drug at 960mg – the dose being used for the registration-directed Phase II portion of the trial – 54 percent experienced a partial response, and the other 46 percent achieved stable disease, meaning their tumors either partially disappeared or were stopped from growing. Stable disease and responses were also observed among patients receiving the drug at the 180mg, 360mg and 720mg doses. Patients in the study were heavily pretreated, having received two prior lines of therapy.
In a phone interview, lead investigator Dr. Ramaswamy Govindan, professor of medicine at Washington University in St. Louis, said the data were encouraging. While researchers have not looked specifically at the KRAS G12C population, Govindan said the general response rate for third-line NSCLC patients receiving chemotherapy by itself is about 3 percent.
The Phase II portion of the study is currently enrolling patients. While uncertain as to what the FDA would want to see, Govindan said if the study shows one-third of patients responding, it will be compelling. “My view is that if I see responses in a third of patients that last many months, that will get my attention,” he said.
Several other companies are developing drugs to target “undruggable” pathways as well, though Amgen remains ahead of the pack. In June, Frontier Medicines launched with a $67 million Series A funding round, with the goal of going after various hard-to-reach targets. And in July, Revolution Medicines raised a $100 million equity round for its own KRAS G12C inhibitor.
The AMG 510 data presented at WCLC update those presented at the American Society of Clinical Oncology meeting in June, which showed five of 10 NSCLC patients achieving a partial response, and four achieving stable disease. In addition, 13 of 18 colorectal cancer patients evaluable at the time achieved stable disease.
Photo: Alaric DeArment, MedCity News