Detailed explanation of the efficacy and role of Osimertinib/Tagrisso

Osimertinib/Tagrisso (Osimertinib) is a targeted drug used to treat patients with multiple EGFR (epidermal growth factor receptor) mutations in non-small cell lung cancer (NSCLC), such as exon 19 deletion or exon 21 L858R mutation, T790M mutation, etc. Osimertinib inhibits tumor cell growth and spread by selectively inhibiting EGFR activity. This targeted targeting can reduce damage to healthy cells and improve treatment effectiveness.

Osimertinib is an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that binds to certain mutated forms of EGFR (T790M, L858R, and exon 19 deletions) that predominate in non-small cell lung cancer (NSCLC) tumors after first-line EGFR-TKIs treatment. As a third-generation tyrosine kinase inhibitor, osimertinib is specific for the gatekeeper T790M mutation, which increases ATP-binding activity with EGFR and leads to poor prognosis in advanced disease. Pharmacokinetic/pharmacodynamic analysis showed that osimertinib at a dose of 80 mg produced a concentration-dependent prolongation of the QTc interval by 14 msec.

Additionally, osimertinib has been shown to avoid wild-typeEGFR during treatment, thereby reducing nonspecific binding and limiting toxicity. Compared with wild-type EGFR, osimertinib has a 200-fold higher affinity for L858R/T790M mutated EGFR molecules in vitro.

Clinical trial studies have shown that the use of osimertinib to treat patients with such mutation-positive non-small cell lung cancer can significantly prolong progression-free survival (PFS) and overall survival (OS). Compared with traditional chemotherapy regimens, osimertinib has better efficacy and tolerability. Common side effects include diarrhea, rash, nausea, fatigue, etc.