Lung cancer: osimertinib halves the risk of death

According to the National Cancer Institute, lung cancer is the 4th most common cancer in France, but it is above all the deadliest. Non-small cell lung cancer is the most common form of lung cancer, accounting for about 85% of cases. Faced with these cancers, the reference treatment when possible is surgery and chemotherapy. However, the recidivism rate remains high. According to a study presented at the ASCO 2023 International Cancer Congress, the use of targeted therapy (already indicated for very advanced forms that do not allow surgery) could reduce the risk of recurrence of some of these cancers.

The special case of EGFR lung cancers

Some lung cancer tumor cells contain a mutation in their DNA that affects certain receptors (epidermal growth factor receptors or EGFR). Schematically, the role of these receptors present on the surface of tumor cells is to tell the tumor when it should grow. When they are mutated (we say that the tumor is “positive for EGFR mutations“), the tumor will be able to grow and spread more quickly.

Between 10 and 25% of Caucasian patients and 40% of Asian patients with non-small cell lung cancer have a mutated EGFR receptor on their surface. These cancers occur more frequently in non-smoking patients, women or in cases of adenocarcinoma. Despite the use of chemotherapy after surgical removal of a tumor, disease recurrence rates remain high and increase with disease stage.

Drugs can now specifically target these receptors, but for a long time their use was limited to metastatic forms (advanced forms of cancer that has already spread to other organs). A study demonstrates the usefulness of one of them, osimertinib (marketed under the name Tagrisso ®) for earlier stages in order to reduce the risk of recurrence after surgery.

A risk of death reduced by half

The international study conducted in 26 countries recruited 682 patients with lung cancer with this EGFR mutation. Two-thirds were female, two-thirds had no smoking history, and two-thirds were Asian. The patients were divided into two groups: the first taking osimertinib once a day and the other a placebo. All were followed for three years.

Result: Five years after surgery, 88% of patients treated were still alive, compared to 78% of patients on placebo. Overall, taking the tablet resulted in a 51% reduction in the risk of death for treated patients, compared to placebo. The side effects of the treatment were rated as “mild to moderate”.

Targeted therapies: towards earlier indications

This targeted therapy had already demonstrated benefits in progression-free survival (time during which the disease does not progress) but the overall survival data further reinforce the interest of this treatment. “This further reinforces the need to identify these patients with available biomarkers at the time of diagnosis and before treatment begins.” said Prof. Roy S. Herbst, deputy director of the Yale Cancer Center and lead author of the study. At a press conference, he added that the drug allows “prevent the disease from spreading to the brain, liver and bones“.

The study is continuing to identify possible residual disease in the patients. At the same time, osimertinib is also being evaluated in other stages of lung cancer, including before surgery. At the same time, this demonstration of the utility of targeted therapy at an earlier stage after surgery paves the way for further studies investigating other tumor-specific ALK and RET mutations for more personalized treatment.