Overview
11 DESCRIPTION Erlotinib a kinase inhibitor, is a quinazolinamine with the chemical name N-(3-ethynylphenyl)-6,7bis(2-methoxyethoxy)-4-quinazolinamine Hydrochloride. Erlotinib contains erlotinib as the hydrochloride salt that has the following structural formula: Erlotinib hydrochloride has the molecular formula C 22 H 23 N 3 O 4 •HCl and a molecular weight of 429.90. The molecule has a pKa of 5.
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Epidermal growth factor receptor (EGFR) is expressed on the cell surface of both normal and cancer cells. In some tumor cells signaling through this receptor plays a role in tumor cell survival and proliferation irrespective of EGFR mutation status. Erlotinib reversibly inhibits the kinase activity of EGFR, preventing autophosphorylation of tyrosine residues associated with the receptor and thereby inhibiting further downstream signaling. Erlotinib binding affinity for EGFR exon 19 deletion or exon 21 (L858R) mutations is higher than its affinity for the wild type receptor. Erlotinib inhibition of other tyrosine kinase receptors has not been fully characterized. 12.
Indications
- 1 INDICATIONS AND USAGE Erlotinib tablet is a kinase inhibitor indicated for: The treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose tumors have epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 (L858R) substitution mutations as detected by an FDA-approved test receiving first-line, maintenance, or second or greater line treatment after progression following at least one prior chemotherapy regimen ( 1.1 ) First-line treatment of patients with locally advanced, unrespectable or metastatic pancreatic cancer, in combination with gemcitabine. ( 1.
Common Doses
- 150 mg
- 100 mg
- 50 mg
- 450 mg
Dosage
2 DOSAGE AND ADMINISTRATION NSCLC: 150mg orally, on an empty stomach, once daily ( 2.2 ) Pancreatic cancer: 100 mg orally, on an empty stomach, once daily. ( 2.3 ) 2.1 Selection of Patients with Metastatic NSCLC Select patients for the treatment of metastatic NSCLC with erlotinib tablets based on the presence of EGFR exon 19 deletions or exon 21 (L858R) substitution mutations in tumor or plasma specimens [see Clinical Studies (14.1 , 14.2) ] . If these mutations are not detected in a plasma specimen, test tumor tissue if available.
Contraindications
- 4 CONTRAINDICATIONS None None ( 4 )
Side Effects
- 6 ADVERSE REACTIONS The following serious adverse reactions, which may include fatalities, are discussed in greater detail in other sections of the labeling: Interstitial Lung Disease (ILD) [see Warnings and Precautions (5.1) ] Renal Failure [see Warnings and Precautions (5.2) ] Hepatotoxicity with or without Hepatic Impairment [see Warnings and Precautions (5.3) ] Gastrointestinal Perforation [see Warnings and Precautions (5.4) ] Bullous and Exfoliative Skin Disorders [see Warnings and Precautions (5.5) ] Cerebrovascular Accident [see Warnings and Precautions (5.
Interactions
- 7 DRUG INTERACTIONS CYP3A4 Inhibitors Co-administration of erlotinib tablets with a strong CYP3A4 inhibitor or a combined CYP3A4 and CYP1A2 inhibitor increased erlotinib exposure. Erlotinib is metabolized primarily by CYP3A4 and to a lesser extent by CYP1A2. Increased erlotinib exposure may increase the risk of exposure-related toxicity [see Clinical Pharmacology (12.3) ] . Avoid co-administering erlotinib tablets with strong CYP3A4 inhibitors (e.g.