Drug reference

Gefitinib

Tyrosine Kinase Inhibitor · Antineoplastic

Tyrosine Kinase InhibitorAntineoplasticATC null

CDSCO approved

EXCRETION

—

not curated

INTERACTIONS

8 major

SEVERE in our sources

PREGNANCY

FDA category + note

Top interactionssee all 12 →

Aminolevulinic AcidSevereDatabaseDDInter
LeflunomideSevereDatabaseDDInter
LomitapideSevereDatabaseDDInter
MipomersenSevereDatabaseDDInter

Mechanism

Gefitinib is a small-molecule, membrane-permeable, ATP-competitive inhibitor of the epidermal growth factor receptor (EGFR/HER1) tyrosine kinase. It binds to the kinase domain's ATP-binding pocket, blocking receptor autophosphorylation and downstream RAS-MAPK and PI3K-AKT signaling cascades that drive tumor cell proliferation. It is most effective in tumors harboring activating EGFR mutations (exon 19 deletions or L858R point mutation), which increase kinase domain sensitivity to inhibition.

Indications

Treatment of locally advanced or metastatic non-small cell lung cancer with activating mutations of epidermal growth factor receptorlung cancer with activating mutations in the epidermal growth factor receptor (EGFR)lung NSCLC (EGFR deletion of exon 19 or L858R mutation)metastatic NSCLC with EGFR mutationsNon-small cell lung cancer with EGFR activating mutationLocally advanced or metastatic lung cancers (after cisplatin and docetaxel failure)

Dosing

Adult: 250 mg once daily by mouth
Renal adjustment: Avoid in severe impairment

Pharmacokinetics

Peak effect

3 to 7 h

Half-life

41 h (terminal)

Bioavailability

about 60% (oral)

Metabolism

CYP3A4 (predominantly)

Contraindications

Severe renal impairment
patients with tumors that do not carry activating EGFR mutations

Side effects

Common

diarrheaskin reactions (>20% of patients)pustular/papular rashdry skinnail changesnauseavomitingpruritusanorexiafatigueSkin rashDiarrhoeaItchingRise in serum transaminase

Serious