gefitinib


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gefitinib

(je-fit-in-ib) ,

Iressa

(trade name)

Classification

Therapeutic: antineoplastics
Pharmacologic: enzyme inhibitors
Pregnancy Category: D

Indications

Patients who are currently benefiting from or have benefited from gefitinib in the past for treatment of non–small-cell lung cancer.

Action

genetic implication Inhibits activation of kinases found in transmembrane cell surface receptors, including epidermal growth factor receptor (EGFR-TK).

Therapeutic effects

Death of rapidly replicating cells, particularly malignant ones.

Pharmacokinetics

Absorption: 60% absorbed following oral administration.
Distribution: Extensively distributed.
Metabolism and Excretion: Mostly metabolized by the liver (CYP3A4 enzyme system); excreted in feces, <4% excreted in urine.
Half-life: 48 hr.

Time/action profile

ROUTEONSETPEAKDURATION
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Contraindications/Precautions

Contraindicated in: Hypersensitivity; Obstetric / Lactation / Pediatric: Pregnancy, lactation, children.
Use Cautiously in: Idiopathic pulmonary fibrosis (↑ risk of pulmonary toxicity);Concurrent use of strong inhibitors of the CYP3A4 enzyme system (may ↑ risk of toxicity).

Adverse Reactions/Side Effects

Central nervous system

  • weakness

Ear, Eye, Nose, Throat

  • aberrant eyelash
  • conjunctivitis
  • corneal erosion/ulcer
  • eye pain
  • ↓ vision

Cardiovascular

  • peripheral edema

Respiratory

  • pulmonary toxicity (life-threatening)
  • dyspnea

Gastrointestinal

  • diarrhea (most frequent)
  • nausea (most frequent)
  • vomiting (most frequent)
  • anorexia
  • hepatotoxicity
  • mouth ulceration

Dermatologic

  • acne (most frequent)
  • dry skin (most frequent)
  • rash (most frequent)
  • pruritus

Metabolic

  • weight loss

Miscellaneous

  • allergic reactions including angioedema (life-threatening)

Interactions

Drug-Drug interaction

Strong inducers of the CYP3A4 enzyme system, including rifampin and phenytoin, ↓ blood levels and effects (consider ↑ dose of gefitinib to 500 mg/day).Strong inhibitors of the CYP3A4 enzyme system, including ketoconazole and itraconazole, ↑ blood levels and effects (use with caution).Absorption and efficacy may be ↓ by drugs that ↑ gastric pH including cimetidine and ranitidine.May ↑ the risk of bleeding with warfarin.Concurrent use with vinorelbine may ↑ risk/severity of neutropenia.

Route/Dosage

Oral (Adults) 250 mg once daily.

Availability

Tablets: 250 mg

Nursing implications

Nursing assessment

  • Assess for signs of pulmonary toxicity (dyspnea, cough, fever). If interstitial lung disease is confirmed, discontinue gefitinib and treat appropriately.
  • Assess patient for eye symptoms such as pain during therapy. May require interruption of therapy and removal of aberrant eyelash. After symptoms and eye changes have resolved, may reinstate therapy.
  • Lab Test Considerations: Monitor liver function tests periodically. May cause ↑ transaminases, bilirubin, and alkaline phosphatase. Discontinue gefitinib if elevations are severe.
    • Monitor for changes in prothrombin time and INR in patients taking warfarin. May cause ↑ levels.

Potential Nursing Diagnoses

Diarrhea (Adverse Reactions)
Impaired skin integrity (Side Effects)
Ineffective breathing pattern (Adverse Reactions)

Implementation

  • Available only through the Iressa Access Program. Patients must be currently on the medication or in an approved study and must sign the Patient Consent Form. Physicians and prescribers must enroll in program.
  • Oral: Administer one tablet daily without regard to food. Tablets can also be dispersed in half a glass of drinking water (noncarbonated). No other liquids should be used. Drop the tablet in the water, without crushing it, stir until the tablet is dispersed (approximately 10 min), and drink the liquid immediately. Rinse the glass with half a glass of water and drink. The liquid can also be administered through a nasogastric tube.
    • May interrupt therapy briefly (14 days) for patients with poorly tolerated diarrhea with dehydration or skin adverse reactions. Follow by restarting 250 mg dose.

Patient/Family Teaching

  • Instruct patient to take gefitinib as directed. Advise patient to read the Instruction Sheet with each Rx refill; new information may be available.
  • Advise patient to notify health care professional promptly if severe persistent diarrhea, nausea, vomiting, or anorexia occur; if shortness of breath or cough occur or worsen; or if eye irritation or other new symptoms develop.
  • Instruct patient to notify health care professional if pregnancy is planned or suspected or if breast feeding.

Evaluation/Desired Outcomes

  • Decrease in size and spread of tumors in non–small-cell lung cancer.

gefitinib

an antineoplastic.
indication This drug is used to treat non-small cell lung cancer.
contraindications Pregnancy and known hypersensitivity to this drug prohibit its use.
adverse effects Adverse effects of this drug include nausea, diarrhea, vomiting, anorexia, mouth ulceration, rash, pruritus, acne, dry skin, cough, dyspnea, peripheral edema, amblyopia, conjunctivitis, eye pain, corneal erosion, and ulcer. Life-threatening side effects include pancreatitis, toxic epidermal neurolysis, angioedema, and interstitial lung disease.
References in periodicals archive ?
She was then given gefitinib, and drainage tube was removed.
The firm has submitted supplemental new drug application based on data from the phase III Flaura trial, in which the product significantly improved progression-free survival compared with first-line EGFR-TKIs, erlotinib or gefitinib, in earlier-untreated patients with locally-advanced or metastatic EGFRm non-small cell lung cancer.
Reportedly, the MAAv submission is based on data from the Phase III FLAURA trial, in which Tagrisso significantly improved progression-free survival (PFS) compared to current 1st-line EGFR-TKIs, erlotinib or gefitinib, in previously-untreated patients with locally-advanced or metastatic EGFRm NSCLC.
Our previous in vitro results showed that Marsdenia tenacissima extract (MTE) overcomes gefitinib resistance in non-small cell lung cancer (NSCLC) cells.
Erlotinib and Gefitinib are selective inhibitors of HER1, whereas Lapatinib can inhibit both HER1 and HER2.
3-5) First-generation tyrosine kinase inhibitors (TKIs) for epidermal growth factor receptor (EGFR) mutations, including gefitinib and erlotinib, significantly improve progression-free survival in stage IV lung cancer patients whose lung cancers are positive for specific driver mutations in the EGFR gene.
Erlotinib and Gefitinib are inhibitors of human epidermal growth factor receptor-1 and the epidermal growth factor receptor tyrosine kinase.
Oncologists currently have at their disposal two EGFR inhibitors: gefitinib (trade name Iressa) and erlotinib (Tarceva).
Gefitinib is a targeted cancer therapy that blocks a tyrosine kinase enzyme to treat non-small cell lung cancers caused by mutations in the epidermal growth factor receptor.
But experts at Cancer Research UK's Paterson Institute discovered tumours could not fight back when it was combined with lung treatment gefitinib.
Dentro de este grupo de las nuevas terapias blanco se encuentra Gefitinib, primer inhibidor del sitio de la tirosinkinasa del receptor del factor de crecimiento epidermico.
One treatment on the NHS in England is a drug called Gefitinib - more commonly known as Iressa - to treat non-small cell lung cancer.