Gefitinib

Film-coated tab: May be taken with or without food. May also be dispersed in ½ glass of plain, non-carbonated water. No other liqd should be used. Drop the tab in water & stir w/o crushing until it disperses (approx 10 min). Drink immediately. Rinse glass w/ another ½ glass of water & drink. Dispersed liqd may also be administered via NG tube.

Lactation.

Patient with history of keratitis, ulcerative keratitis or severe dry eyes; recent corneal surgery, wearing of contact lenses; risk factors for gastrointestinal perforation (e.g. history of gastrointestinal ulceration, age, smoking, bowel metastases). Renal CrCl ≤20 mL/min and moderate to severe hepatic impairment. Pregnancy. Concomitant use with CYP3A4 inducers. CYP2D6 poor metabolisers. Patient Counselling This drug may cause asthenia, if affected, do not drive or operate machinery. Monitoring Parameters Establish EGFR mutation status prior to treatment initiation. Monitor LFTs (e.g. ALT, AST, bilirubin), renal function tests, and serum electrolytes at baseline and periodically thereafter; INR or prothrombin time in patients receiving warfarin. Assess for symptoms of gastrointestinal perforation, dermatologic, ocular, or pulmonary toxicity especially in CYP2D6 poor metabolisers and patients with hepatic impairment.

Significant: Gastrointestinal effects (e.g. severe or persistent diarrhoea, nausea, vomiting, anorexia, gastrointestinal perforation), dermatologic toxicity (e.g. toxic epidermal necrolysis, Stevens-Johnson syndrome, erythema multiforme, dermatitis bullous), ocular toxicity (e.g. keratitis, corneal erosion, abnormal eyelash growth, conjunctivitis, blepharitis, dry eyes); elevated ALT/AST and bilirubin. Gastrointestinal disorders: Nausea, vomiting, stomatitis, dry mouth, pancreatitis. General disorders and administration site conditions: Asthenia, pyrexia. Immune system disorders: Urticaria, angioedema. Investigations: Increased blood creatinine. Metabolism and nutrition disorders: Anorexia, dehydration. Renal and urinary disorders: Proteinuria, cystitis. Skin and subcutaneous tissue disorders: Pustular rash, pruritus, dry skin, skin fissures, erythema, nail disorder, alopecia. Vascular disorders: Epistaxis, haematuria.
Potentially Fatal: Interstitial lung disease (ILD) or ILD-like reactions (e.g. acute respiratory distress syndrome, lung infiltration, pneumonitis, pulmonary fibrosis), CNS haemorrhage. Rarely, hepatic failure.

Decreased plasma concentration and efficacy with CYP3A4 inducers (e.g. rifampicin, phenytoin, carbamazepine, barbiturates). Increased plasma levels and risk of adverse effects with potent CYP3A4 inhibitors (e.g. ketoconazole, protease inhibitors, clarithromycin). Increased risk of elevated INR and bleeding events with warfarin. Reduced plasma concentrations, bioavailability and efficacy with drugs that elevate gastric pH (e.g. PPIs, H₂-receptor antagonists, antacids). May exacerbate neutropenic effects of vinorelbine. May increase exposure of metoprolol. Increased risk of gastrointestinal perforation with NSAIDs or steroids.

Targeted Cancer Therapy

L01EB01 - gefitinib