Once-a-day use of the targeted cancer pill Tagrisso (osimertinib) cut the five-year death rate in half for a subset of patients with early-stage lung cancer, a new clinical trial shows.
The results could have major implications for patients whose cancers carry a mutation in a gene known as EGFR, which is implicated in the out-of-control cellular growth driving a tumor. Tagrisso appears to short-circuit this excessive growth.
The new trial involved 682 patients with stages IB, II or IIIA non-small cell lung cancers (NSCLC). About 85% of lung cancers are NSCLCs. All patients in the study had cancers with EGFR mutations.
"We have been using one-size-fits-all adjuvant chemotherapy for every patient with lung cancer despite a decade of advances in targeted treatments for select groups of patients that result in dramatically better outcomes,"noted Dr. Nathan Pennell, an oncologist and professor of medicine at the Cleveland Clinic Lerner College of Medicine in Ohio.
"In a first for the lung cancer field, adjuvant osimertinib unequivocally improves survival in people with resected [surgically treated] EGFR-mutated non-small cell lung cancer,"Pennell said in a news release from the American Society of Clinical Oncology (ASCO).
"This should be the new standard of care for these patients,"Pennell added.
The study was presented Sunday at ASCO's annual meeting, in Chicago. It was also published simultaneously in the New England Journal of Medicine.
The new trial was funded by Tagrisso's maker, AstraZeneca, and led by Dr. Roy Herbst, deputy director of Yale Cancer Center and assistant dean for translational research at Yale School of Medicine, in New Haven, Conn.
The study had a global reach: Patients came from 26 different countries across North America, Europe, Asia-Pacific and South America. About two-thirds of the patients were women, and patients ranged in age from 30 to 86 (average age was 64 among those taking Tagrisso).
In addition to receiving standard care, patients were randomly assigned to receive either an 80 milligram (mg) pill of Tagrisso once daily or an inactive placebo for up to three years. Two-thirds of patients in the group receiving Tagrisso completed the full three years of treatment, compared to 41% of those taking placebo.
The results were heartening: 88% of those on Tagrisso were still alive five years after their initial surgery for their lung cancer, compared to 78% of those on placebo. Put another way, that translated into a 51% reduction in risk of death for those on Tagrisso versus those who were not.
This survival benefit was seen across all stages of cancer included in the trial, and it was consistent whether or not patients had already received standard chemotherapy before joining the trial.
"Overall survival has historically been considered the gold standard efficacy endpoint for randomized adjuvant clinical trials,"Herbst noted. The trial results "will broaden treatment access for patients with EGFR-mutated non-small cell lung cancer,"he added.
The same team had already reported three years ago that Tagrisso helped prevent tumors from recurring and/or spreading to the brain, liver and bone.
Despite recent drops in smoking rates, lung cancer remains the number one cancer killer of Americans, taking the lives of over 136,000 people in 2020, according to the U.S. Centers for Disease Control and Prevention.
According to ASCO, anywhere from 10% to 25% of lung cancer cases in the United States contain EGFR mutations. Even after surgical removal of the tumor and standard chemotherapy, disease recurrence rates for stage IB--IIIA NSCLCs remain high.
Tagrisso belongs to a new class of cancer drugs known as tyrosine kinase inhibitors (TKI). According to ASCO, it's "the first targeted agent to be approved by the U.S. Food and Drug Administration as an adjuvant treatment for resected stage IB--IIIA EGFR[-mutated] NSCLC." The drug was approved for use in late-stage lung cancers in 2015.
Side effects did occur more often in the Tagrisso group versus those taking placebo: "Adverse events"(most commonly diarrhea, skin conditions and cough) prompted 13% of patients to stop treatment in the Tagrisso group, versus 3% of those taking placebo.
According to ASCO, Tagrisso is also being studied at other stages of NSCLC, including its use before surgery.
The totality of the data from his team's research "instills confidence that adjuvant osimertinib is the standard of care for patients with resected EGFR[-mutated] stage IB--IIIA non-small-cell lung cancer,"Herbst said.
He also believes that testing patients for the presence of the EGFR mutation in their tumors needs to become more standard.
The study "further reinforces the need to identify these patients with available biomarkers at the time of diagnosis and before treatment begins,"Herbst said.
More information
Find out more about lung cancer treatment at the American Cancer Society.
SOURCE: American Society of Clinical Oncology, news release, June 6, 2023
