[11C]osimertinib

[11C]osimertinib is a radiolabeled derivative of osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). While osimertinib (brand name Tagrisso) is a therapeutic agent for non-small cell lung cancer (NSCLC), [11C]osimertinib is primarily used as a positron emission tomography (PET) tracer. It is designed to non-invasively assess the brain exposure and distribution of osimertinib, particularly in patients with NSCLC and brain metastases. The drug's mechanism of action involves selectively and irreversibly binding to mutated forms of EGFR, including TKI-sensitizing mutations (e.g., exon 19 deletions, L858R) and the T790M resistance mutation, while largely sparing wild-type EGFR. This allows for the visualization of EGFR-mutated tumor cells in the brain using PET imaging. The development of osimertinib was led by AstraZeneca.