GEFIREN (GEFITINIB) 250MG 30`S

Gefiren contains gefitinib, a targeted therapy that blocks the EGFR (epidermal growth factor receptor) tyrosine kinase enzyme — a protein that EGFR-mutant cancer cells rely on to grow and divide. By disrupting this signaling pathway, gefitinib induces cancer cell death and arrests tumor progression.

It is indicated as first-line monotherapy for locally advanced or metastatic non-small cell lung cancer (NSCLC) in adults whose tumors carry confirmed activating EGFR mutations — specifically exon 19 deletions or exon 21 L858R substitutions.

Recommended dose: 250mg once daily, taken with or without food, at the same time each day. Swallow tablets whole with water.

•       Missed dose: take as soon as remembered, unless the next dose is within 12 hours — in that case, skip the missed dose. Never double up.

•       Cannot swallow whole: dissolve in half a glass of still water, stir for approximately 15 minutes, drink immediately, then rinse and drink the glass residue.

•       Dose modifications for Grade 3+ toxicity (rash, diarrhoea, ILD): interrupt therapy until resolved to Grade 1 or less; restart at 250mg. Recurrence warrants permanent discontinuation.

•       Hepatic impairment: no routine dose adjustment for mild-moderate impairment; use with caution in severe impairment (Child-Pugh C).

•       Known severe hypersensitivity to gefitinib

•       Pre-existing interstitial lung disease or pulmonary fibrosis — use with extreme caution; ILD risk is higher

•       Severe hepatic impairment — risk of significant drug accumulation

•       Pregnancy: Gefitinib is embryotoxic and teratogenic. Effective contraception is required during treatment and for at least 1 month after the last dose.

•       Strong CYP3A4 inducers (rifampicin, phenytoin, carbamazepine, St. John's Wort): significantly reduce gefitinib plasma levels. Consider a dose increase to 500mg if co-administration is unavoidable.

•       Proton pump inhibitors (omeprazole, pantoprazole): raise gastric pH and reduce gefitinib absorption by approximately 47%. Use H2 blockers or antacids at separate times where possible.

•       Warfarin: gefitinib inhibits CYP2C9, increasing warfarin effect. Monitor INR weekly for the first month, then monthly.

•       Strong CYP3A4 inhibitors (itraconazole, ketoconazole): increase gefitinib exposure — monitor for increased toxicity.

•       Store below 30°C in original blister packaging. Protect from moisture and heat. Keep out of reach of children and pregnant women.

Q: What is Gefiren used for?

Gefiren treats non-small cell lung cancer (NSCLC) in adults whose tumours carry specific EGFR gene mutations. It is a targeted therapy — it selectively attacks cancer cells with a specific molecular abnormality rather than all rapidly dividing cells.

Q: Do I need a genetic test before starting?

Yes, without exception. Gefitinib only works if your tumour carries certain EGFR mutations (exon 19 deletion or L858R). The test is performed on a biopsy sample or a blood test (liquid biopsy). Your oncologist will arrange this before prescribing.

Q: What should I do if I develop breathlessness?

Stop taking Gefiren immediately and go to the hospital or contact your oncologist the same day. New breathlessness, dry cough, or fever may indicate interstitial lung disease (ILD) — a rare but potentially life-threatening complication requiring urgent assessment.

Q: Does gefitinib interact with my stomach acid medicines?

Yes — proton pump inhibitors like omeprazole reduce gefitinib absorption significantly. Discuss alternatives with your oncologist. If a PPI is essential, take it at different times from gefitinib where possible.