Xiuning Le remembers the patient whose lung tumors shrank dramatically within weeks of starting a new drug—no radiation, no chemotherapy, just a pill tailored to the unique shape of their cancer. That drug, firmonertinib, is now offering fresh hope to people with a rare form of lung cancer long overlooked by treatment guidelines.
Lung cancer with uncommon EGFR mutations has always been a puzzle. Standard therapies often fail, and doctors have had little evidence to guide their choices. But now, a trial at MD Anderson Cancer Center is turning molecular insights into real-world results. The FURTHER trial tested firmonertinib on 60 patients with a specific subset of EGFR mutations known as PACC—short for P-loop and αC-helix compressing mutations. These account for about 12% of all EGFR-mutant lung cancers, yet until now, they’ve had no targeted treatment.
The results were striking. Patients taking 240 mg of firmonertinib daily went a median of 16 months without their cancer worsening—nearly twice as long as those on the lower dose. Among patients who hadn’t been treated before, two-thirds responded to the higher dose, with tumors shrinking significantly. Even more remarkable: in lab models, firmonertinib blocked tumor growth by over 90% across multiple PACC subtypes.
One of the most promising aspects was its effect on brain metastases—cancer that had spread to the brain, a common and dangerous complication. In 17 patients with brain lesions, nearly half saw their tumors shrink, and 41% had complete responses, meaning no detectable cancer remained in the brain. This is especially meaningful because many drugs can’t cross the blood-brain barrier effectively.
Researchers also tracked tumor DNA floating in the blood, known as ctDNA. After treatment, 80% of evaluable patients had no trace of the PACC mutation in their blood. Those who cleared the DNA lived longer without progression and responded better—suggesting a simple blood test could one day help doctors monitor treatment in real time.
The success of this structure-guided approach—matching drugs to the 3D shape of a mutation, not just its genetic location—has already sparked the next phase. The global Phase III ALPACCA trial is now comparing firmonertinib to standard therapies as a first-line treatment. If it confirms these results, a new standard of care could emerge—one built not just on genetics, but on the physical structure of cancer itself.