Research on the potential application of osimertinib (Tagrisso) in the treatment of breast cancer

Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor currently mainly used for the treatment of EGFR-mutant non-small cell lung cancer (NSCLC). However, with the in-depth research on molecular targeted therapy, the potential application of osimertinib in breast cancer, especially breast cancer with abnormal expression of HER2 or EGFR, has gradually attracted attention. Laboratory studies have shown that a subset of breast cancer cells have abnormal activation of the EGFR or HER2 signaling pathways, and these abnormalities may lead to tumor proliferation and drug resistance. Osimertinib is expected to inhibit tumor growth in these patients by irreversibly inhibiting EGFR signaling.

Preliminary in vitro experiments have shown that osimertinib can inhibit proliferation and induce apoptosis in some breast cancer cell lines. Studies have shown that for breast cancer cells with high EGFR expression or T790M mutation-positive, osimertinib can significantly reduce cell activity and block related downstream signaling pathways, such as PI3K/AKT and MAPK pathways, thereby inhibiting tumor growth. Animal model studies have also preliminarily confirmed that osimertinib can delay tumor progression in breast cancer xenograft models and has a tolerable safety profile.

Clinically, it is still in the early exploratory stage. Some small clinical trials and case reports suggest that osimertinib may bring a certain remission effect to patients with metastatic breast cancer with abnormal expression of EGFR. Researchers are also trying to combine osimertinib with other targeted drugs or chemotherapy drugs to enhance efficacy and delay the development of drug resistance. This strategy is particularly suitable for breast cancer patients who are resistant to or relapsed with traditional HER2-targeted therapy and provides new treatment ideas.
Overall, the application of osimertinib in breast cancer is still in the early stages of research, but its targeting effect on the abnormal EGFR signaling pathway provides potential treatment possibilities for breast cancer patients. In the future, it is necessary to verify its safety and efficacy through large-scale clinical trials, and to clarify the applicable population, dosage and combination treatment regimen. If research progresses, osimertinib is expected to become a new option for precision treatment of breast cancer, especially for drug-resistant or high-risk patients.
Reference: https://www.ema.europa.eu/en/homepage