For the first time, patients who have non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations have a targeted therapy option approved for adjuvant use. This is a considerable advancement in helping those patients who might experience disease progression after initial EGFR treatment and even develop resistance to that treatment. While EGFR inhibitors are able to shrink tumors, cancer cells may go on to develop another mutation in the EGFR gene. Studies have shown that post-surgery use of Tagrisso (osimertinib)
may successfully delay disease recurrence in patients with localized NSCLC.
Accounting for up to 85% of all lung cancers, NSCLC itself has main subtypes that include adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. Preventing metastases is critical to long-term survival in all types. Unfortunately, it is common for patients to develop disease recurrence even if complete resection was possible. Research for osimertinib presented at the recent American Society of Clinical Oncology annual meeting demonstrated a capability to reduce the recurrence of disease or death by 83%, compared with placebo, in stage II-IIIA patients after surgery. It also showed that patients with stage II-IIIA NSCLC achieved a 90% survival rate for two years with no disease recurrence, compared with 44% who received a placebo. These results signify dramatic improvement for prognosis in patients with the condition.
Osimertinib’s recommended dosing for adjuvant treatment of early-stage NSCLC is 80mg orally once per day. Similar to other targeted therapies for lung cancer, there are possible adverse reactions involving dermatological, gastrointestinal, and hematological systems. Its most common (>20%) adverse reactions, including laboratory abnormalities, are lymphopenia, leukopenia, thrombocytopenia, diarrhea, anemia, musculoskeletal pain, nail toxicity, neutropenia, dry skin, stomatitis, fatigue, and cough. Overall, there have been favorable tolerability data, adding to osimertinib’s potential as a promising therapy for many patients. Recent updates to NCCN Guidelines for NSCLC
have incorporated recommendations for osimertinib as postoperative or adjuvant therapy. So far, results like those seen with osimertinib are encouraging and undoubtedly clinically meaningful for patients with NSCLC.
Advancements like the treatment potential of osimertinib as targeted therapy within an earlier state of NSCLC reinforce the benefit of testing to identify patients who are candidates for targeted therapy. According to the National Cancer Institute, the effect of immune checkpoint inhibitors on NSCLC survival is significant. It reports that NSCLC incidence has fallen in the US in recent years and attributes the improvement to recent advances in treatment. As genetic testing for EGFR mutations and other gene targets increases, and as guidelines and further approvals are achieved after continued research and understanding of long-term results, exciting advances in related targeted therapy will continue.