Stage 4 adenocarcinoma non-small cell (aNSCLC) lung cancer treatment has been dictated in recent years by the genetic mutation, or biomarker. Patients received either chemotherapy, immunotherapy, a combination of the two, or a personalized targeted therapy depending on the biomarkers in their cancer. During this period, only a few biomarkers had FDA-approved targeted therapies. Unfortunately, KRAS was not one of them.

KRAS is the most common genetic mutation found in aNSCLC, and it has several different subtypes of specific mutations. The most common of the subtypes is KRAS G12C. KRAS G12C makes up 40 percent of all KRAS mutations (and 13 percent of all aNSCLC mutations). For comparison, EGFR mutations make up 14 percent of aNSCLC mutations.

New hope for patients with KRAS mutations.

Without personal targeted therapy, “our treatments for KRAS have been immunotherapy and chemotherapy—and that’s it,” said Dr. Stephen Liu, associate professor of medicine and director of thoracic oncology and development therapeutics at Georgetown Lombardy Comprehensive Cancer Center. Speaking at GO2 for Lung Cancer’s June 15 Living Room on biomarker testing, he explained that this meant that more than one-third of aNSCLC patients with an identified mutation did not have any targeted treatment options.

However, scientists are hard at work developing drugs to target KRAS. This process has been far more challenging than for other biomarkers because of how difficult it is to directly affect the KRAS gene in a patient’s tumor cells.

Despite this difficulty, drugs targeting the G12C variant of KRAS went into clinical trials—and one received approval in May. This new approval has breathed fresh air into the treatment landscape for thousands of patients in the U.S.

One such patient: Cecily Hatchitt of Merlin, Oregon. Hatchitt describes the advent of KRAS G12C drugs “like a personal email to you. It’s intended just for me with G12C and anybody else who might have G12C.”

Instead of receiving general treatments, Hatchitt and other patients like her now get a drug designed specifically for their type of lung cancer. Since going on targeted therapy, Hatchitt is delighted that she can now travel. “I am no longer tied down to a clinic with infusions because this therapy is actually a pill that I can take,” she said.

Determining your eligibility for KRAS targeted personal therapy.

As with any targeted therapy, the only way to receive a KRAS G12C drug is to have biomarker testing to identify that you have the correct mutation. The best type of test to receive? A comprehensive biomarker test. As Liu explained, “Knowing you are KRAS positive is not enough. As with EGFR, you need the details. You need the specific mutation. A PCR test isn’t going to tell you whether it’s a C or a D. So you need to know exactly what type of test you’re doing.”

All lung cancer patients should receive comprehensive testing in order to receive the best treatment possible. In addition to possibly identifying a targetable mutation and receiving targeted therapy, comprehensive biomarker tests allow you and other patients to be eligible for cutting-edge clinical trials to improve personalized and precision medicine.