Amgen sends first KRAS drug to the FDA, approval could follow swiftly

It only took a decade or 3, but KRAS will finally have its day in court.

Amgen announced late Wednesday that they had submitted their KRAS inhibitor sotorasib to the FDA for approval in patients with metastatic non-small cell lung cancer and a KRAS G12C mutation. An approval could come swiftly, as the agency has given the molecule breakthrough designation and included it in their rare “real-time oncology review” program — the same program that, in 2018, allowed the FDA to OK a Novartis drug in less than a month.

Although excitement has cooled in the past year, the submission marks a pivotal moment in a decades-long quest to drug one of the most ubiquitous and hard-to-hit cancer mutations. Amgen surprised competitors when they became the first company to put such an inhibitor in the clinic in 2018, and they have since led the pack on data, most recently showing a 32.3% response rate across 59 patients at ESMO. The median progression-free survival rate was 6.3 months overall, but 10.9 months among responders.

An approval would bode well not only for Amgen’s long-term cancer pipeline, which now hinges greatly on trials testing KRAS in combination with other drugs, but also for their rival Mirati. The KRAS-focused California biotech has remained a step behind Amgen but shown similar or better results in NSCLC. Pooling data from two trials, they reported a 45% response rate in 51 patients at ESMO.

Those two data tranches could set the stage for two approved KRAS drugs in short order. Still, the targeted drugs’ overall impact remains uncertain. Both the Amgen and Mirati molecules have disappointed in other tumors, and while considerable dollars are now pouring into combination approaches — with Relay and Roche recently joining the fray in a high-profile partnership — they remain unproven. Data from those studies could ultimately determine how great an impact the drug and the decades-long quest to develop them will have.