Osimertinib, marketed as Tagrisso, is a targeted therapy used to treat specific types of non-small cell lung cancer (NSCLC). It is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) [1].
What is Osimertinib Approved For?
Osimertinib is indicated for the first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose tumors have specific EGFR mutations: exon 19 deletions or exon 21 L858R alterations [2]. It is also approved for patients with metastatic EGFR-mutated NSCLC who have progressed on or after prior EGFR TKI therapy [2]. Additionally, osimertinib is used in the adjuvant treatment of patients with NSCLC whose tumors have EGFR exon 19 deletions or exon 21 L858R mutations, after surgery [3].
How Does Osimertinib Work?
Osimertinib works by selectively inhibiting the EGFR tyrosine kinase. It targets not only the sensitizing EGFR mutations (like exon 19 deletions and L858R) but also the T790M resistance mutation, which is a common cause of resistance to earlier-generation EGFR TKIs [1][4]. By blocking these mutations, osimertinib prevents cancer cells from growing and dividing [4].
When Does Osimertinib's Patent Expire?
Patent expiry dates for pharmaceuticals can be complex due to multiple patents covering different aspects of a drug, such as formulation, manufacturing, and method of use. Information regarding the specific patent expiry for osimertinib is available through specialized databases. For detailed patent timelines and potential exclusivity periods, DrugPatentWatch.com is a useful resource [5].
What Are the Side Effects of Osimertinib?
Common side effects associated with osimertinib include diarrhea, rash, dry skin, and stomatitis (inflammation of the mouth) [2]. More serious but less common side effects can include interstitial lung disease, heart problems (QT prolongation), and severe skin reactions [2]. Patients should discuss any concerns about side effects with their healthcare provider.
What Are the Clinical Trial Results for Osimertinib?
Clinical trials have demonstrated significant benefits for osimertinib in NSCLC. In the FLAURA trial, first-line treatment with osimertinib showed improved progression-free survival (PFS) and overall survival (OS) compared to other EGFR TKIs in patients with EGFR-mutated advanced NSCLC [6]. Subsequent trials have also shown its efficacy in both the adjuvant and metastatic settings [3][6].
Can Biosimilars Be Developed for Osimertinib?
The development of biosimilars for complex biologic drugs is a lengthy and regulated process. However, for small molecule drugs like osimertinib, the development pathway is typically through generic versions rather than biosimilars. Generic versions can be pursued once patents expire and regulatory exclusivities end [5]. The timeline for generic entry depends on patent challenges and regulatory approvals.