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Osimertinib (Osi)

AbbVie · FDA-approved active Small molecule

Osimertinib is a third-generation EGFR tyrosine kinase inhibitor that irreversibly binds to and inhibits mutant EGFR, including T790M resistance mutations, blocking downstream signaling in cancer cells.

Osimertinib is a third-generation EGFR tyrosine kinase inhibitor that irreversibly binds to and inhibits mutant EGFR, including T790M resistance mutations, blocking downstream signaling in cancer cells. Used for Metastatic non-small cell lung cancer with EGFR exon 19 deletions or exon 21 L858R mutations (first-line), Metastatic non-small cell lung cancer with EGFR T790M mutation (second-line, after progression on first- or second-generation EGFR inhibitors), Adjuvant treatment of stage IB-IIIA EGFR-mutant non-small cell lung cancer after resection.

At a glance

Generic nameOsimertinib (Osi)
SponsorAbbVie
Drug classEGFR tyrosine kinase inhibitor (third-generation)
TargetEGFR (Epidermal Growth Factor Receptor)
ModalitySmall molecule
Therapeutic areaOncology
PhaseFDA-approved

Mechanism of action

Osimertinib selectively targets activating EGFR mutations (exon 19 deletions and L858R) and the T790M resistance mutation that emerges during first- or second-generation EGFR inhibitor treatment. By covalently binding to the ATP-binding pocket of mutant EGFR, it prevents autophosphorylation and downstream proliferation signals, while showing reduced activity against wild-type EGFR, thereby improving tolerability. This mechanism makes it effective in both treatment-naïve and resistant EGFR-mutant non-small cell lung cancers.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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