Osimertinib is a targeted therapy medication used primarily to treat non-small cell lung cancer (NSCLC) that has specific mutations in the EGFR gene. It works by inhibiting the activity of the mutated EGFR protein, which helps to slow down or stop the growth of cancer cells. Approved by the FDA, Osimertinib is often prescribed for patients whose cancer has progressed after other treatments. It is taken orally in pill form, making it convenient for patients. Common side effects may include diarrhea, rash, and fatigue, but many patients tolerate it well.