Gefitinib

The epidermal growth factor receptor (EGFR) is expressed on the cell surface of both normal and cancer cells and plays a role in the processes of cell growth and proliferation. Some EGFR activating mutations (exon 19 deletion or exon 21 point mutation L858R) within NSCLC cells have been identified as contributing to the promotion of tumor cell growth, blocking of apoptosis, increasing the production of angiogenic factors and facilitating the processes of metastasis.

• Gefitinib tablets are indicated for the first-line 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 [ see Clinical Studies (14) ]. Limitation of Use: Safety and efficacy of gefitinib tablets have not been established in patients with metastatic NSCLC whose tumors have EGFR mutations other than exon 19 deletions or exon 21 (L858R) substitution mutations [ see Clinical Studies (14) ].ICD-10: C34.90

• None. None.contraindicated

Recommended dose is 250 mg orally, once daily with or without food. (2.2) 2.1 Patient Selection Select patients for the first-line treatment of metastatic NSCLC with gefitinib tablets based on the presence of EGFR exon 19 deletions or exon 21 L858R mutations in their tumor or plasma specimens[ see Indications and Usage (1) , Clinical Studies (14) ]. If these mutations are not detected in a plasma specimen, test tumor tissue if feasible. Information on FDA-approved tests for the detection of EGFR mutations in NSCLC is available at: http://www.fda.gov/CompanionDiagnostics . 2.2 Recommended Dose The recommended dose of gefitinib tablets is 250 mg orally once daily with or without food until disease progression or unacceptable toxicity. Do not take a missed dose within 12 hours of the next dose. 2.3 Administration to Patients Who Have Difficulty Swallowing Solids Immerse gefitinib tablets in 4 to 8 ounces of water by dropping the tablet in water, and stir for approximately 15 minutes. Immediately drink the liquid or administer through a naso-gastric tube. Rinse the container with 4 to 8 ounces of water and immediately drink or administer through the naso-gastric tube.

•Interstitial lung disease (ILD): ILD occurred in patients taking gefitinib tablets. Withhold gefitinib tablets for worsening of respiratory symptoms. Discontinue gefitinib tablets if ILD is confirmed. ( 2.4 , 5.1 ) •Hepatotoxicity: Obtain periodic liver function testing. Withhold gefitinib tablets for Grade 2 or higher for ALT and/or AST elevations. Discontinue for severe hepatic impairment. ( 2.4 , 5.2 ) •Gastrointestinal perforation: Discontinue gefitinib tablets for gastrointestinal perforation. ( 2.4 , 5.3 ) •Diarrhea: Withhold gefitinib tablets for Grade 3 or higher diarrhea. ( 2.4 , 5.4 ) •Ocular Disorders including Keratitis: Withhold gefitinib tablets for signs and symptoms of severe or worsening ocular disorders including keratitis. Discontinue for persistent ulcerative keratitis. ( 2.4 , 5.5 ) •Bullous and Exfoliative Skin Disorders: Withhold gefitinib tablets for Grade 3 or higher skin reactions or exfoliative conditions. ( 2.4 , 5.6 ) •Embryo-fetal Toxicity: Can cause fetal harm. Advise of potential risk to a fetus and use of effective contraception. ( 5.7 , 8.1 , 8.3 ) 5.1 Interstitial Lung Disease (ILD) ILD or ILD-like adverse drug reactions (e.g., lung infiltration, pneumonitis, acute respiratory distress syndrome, or pulmonary fibrosis) occurred in 1.3% of the 2462 patients who received gefitinib tablets across clinical trials; of these, 0.7% were Grade 3 or higher and 3 cases were fatal. Withhold gefitinib tablets and promptly investigate for ILD in any patient who presents with worsening of respiratory symptoms such as dyspnea, cough and fever.

The following adverse drug reactions are discussed in more detail in other sections of the labeling: • Interstitial Lung Disease [ see Warnings and Precautions (5.1) ] • Hepatotoxicity [ see Warnings and Precautions (5.2) ] • Gastrointestinal Perforation [ see Warnings and Precautions (5.3) ] • Severe or Persistent Diarrhea [ see Warnings and Precautions (5.4) ] • Ocular Disorders including Keratitis [ see Warnings and Precautions (5.5) ] • Bullous and Exfoliative Skin Disorders [ see Warning and Precautions (5.6) ] The most commonly reported adverse drug reactions (ADRs), reported in more than 20% of the patients and greater than placebo were skin reactions and diarrhea. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact QILU PHARMA, INC. at 484-838-0633 / 484-875-3013 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of gefitinib tablets is based on the data from 2462 patients with NSCLC who received gefitinib tablets 250 mg daily monotherapy in three randomized clinical studies (Study 2, Study 3 and Study 4). Patients with a history of interstitial lung disease, drug-induced interstitial disease, radiation pneumonitis that required steroid treatment or any evidence of clinically active interstitial lung disease were excluded from these studies.

Lactation: Discontinue breast-feeding. (8.2) 8.1 Pregnancy Risk Summary Based on its mechanism of action and animal data, gefitinib tablets can cause fetal harm when administered to a pregnant woman. In animal reproductive studies, oral administration of gefitinib from organogenesis through weaning resulted in fetotoxicity and neonatal death at doses below the recommended human dose ( see Animal Data ). Advise pregnant women of the potential hazard to a fetus or potential risk for loss of the pregnancy. The background risk of major birth defects and miscarriage for the indicated population is unknown; however, the background risk in the U.S. general population of major birth defects is 2-4% and miscarriage is 15-20% of clinically recognized pregnancies. Data Animal Data A single dose study in rats showed that gefitinib crosses the placenta after an oral dose of 5 mg/kg (30 mg/m 2 , about 0.2 times the recommended human dose on a mg/m 2 basis). When pregnant rats were treated with 5 mg/kg from the beginning of organogenesis to the end of weaning there was a reduction in the number of offspring born alive. This effect was more severe at 20 mg/kg (approximate the human clinical dose on a mg/m 2 basis) and was accompanied by high neonatal mortality soon after parturition.

Metabolism

Absorption and Distribution The mean oral bioavailability of gefitinib is 60%, with peak plasma levels occurring 3-7 hours after dosing. Food does not alter gefitinib bioavailability to a clinically meaningful extent.

Twenty three patients were treated weekly with doses from 1500 mg to 3500 mg, and gefitinib tablets exposure did not increase with increasing dose. Adverse events were mostly mild to moderate in severity, and were consistent with the known safety profile of gefitinib tablets. In the event of suspected overdose, interrupt gefitinib tablets, institute supportive care, and observe until clinical stabilization. There are no specific measures/treatments that should be taken following gefitinib tablets overdosing.

• Jul 13, 2015NDANDA206995Astrazeneca
• Feb 13, 2023ANDAANDA211591Qilu Pharm Hainan
• Apr 26, 2023ANDAANDA208913Actavis Labs Fl Inc
• May 31, 2023ANDAANDA212827Natco

1. 1Malignant Neoplasm Progression1,81720%
2. 2Drug Resistance1,24914%
3. 3Diarrhoea89910%
4. 4Death7558.4%
5. 5Rash6397.1%
6. 6Disease Progression4585.1%
7. 7Interstitial Lung Disease4194.7%
8. 8Nausea3784.2%
9. 9Metastases To Central Nervous System3764.2%
10. 10Dyspnoea3303.7%
11. 11Vomiting3253.6%
12. 12Drug Ineffective2973.3%
13. 13Pneumonia2703.0%
14. 14Pyrexia2703.0%
15. 15Acquired Gene Mutation2582.9%

Recent PubMed references pinned to Gefitinib as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

• Cepharanthine Reverses Gefitinib Resistance in NSCLC by Concurrently Inhibiting AKT/P70S6K Survival Signaling and Activating STING-Mediated Immune Response.
  Chemical biology & drug design · 2026 · Kang LP, Chen HH, Lv TT, et al.
  PMID 42059424DOI 10.1111/cbdd.70298
• GC/MS and LC/MS Metabolomic Analysis of Gefitinib in Liver Cancer.
  Biomedical chromatography : BMC · 2026 · Li D, Zhang Y, Chen S, et al.
  PMID 42055538DOI 10.1002/bmc.70470
• Galangin Overcomes Gefitinib and Sotorasib Resistance in Non-small Cell Lung Cancer by Inhibiting Efferocytosis.
  Journal of agricultural and food chemistry · 2026 · Su TH, Cao J, Ding XX, et al.
  PMID 42007639DOI 10.1021/acs.jafc.5c17222
• Artesunate reverses gefitinib resistance in lung adenocarcinoma by inducing ferroptosis and suppressing the Wnt/β-catenin pathway.
  European journal of pharmacology · 2026 · Zhang B, Lv X, Liu M, et al.
  PMID 41967624DOI 10.1016/j.ejphar.2026.178856
• 3-Formylchromone attenuates urethane-induced lung carcinogenesis and enhances gefitinib anti-tumor response via modulation of IL-6/JAK1/STAT3/cyclin D1 signaling.
  Toxicology mechanisms and methods · 2026 · Azouz AA, Khalaf A, Hussein R, et al.
  PMID 41964278DOI 10.1080/15376516.2026.2645332
• Yifei Sanjie pill combined with gefitinib reduces the progression of EGFR-TKIs-resistant non-small cell lung cancer via YAP/ANKRD1 axis.
  Phytomedicine : international journal of phytotherapy and phytopharmacology · 2026 · Yuan Y, Zhou R, Ye Z, et al.
  PMID 41865688DOI 10.1016/j.phymed.2026.158003
• [Expression of Concern] Interference of STAT 5b expression enhances the chemo‑sensitivity of gastric cancer cells to gefitinib by promoting mitochondrial pathway‑mediated cell apoptosis.
  Oncology reports · 2026 · Sun T, Jia Y, Xiao D, et al.
  PMID 41685596DOI 10.3892/or.2026.9075
• Cost-effectiveness analysis of rezivertinib and gefitinib in patients with EGFR-mutated advanced non-small cell lung cancer.
  Expert review of pharmacoeconomics & outcomes research · 2026 · Kou C, Wu H, Liu L, et al.
  PMID 41630689DOI 10.1080/14737167.2026.2626573

The 10 most recently updated of 425 ClinicalTrials.gov registrations naming Gefitinib as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Study to Allow Patients Previously Participating in a Novartis Sponsored Trial to Continue Receiving Capmatinib Treatment as Single Agent or in Combination With Other Treatments or the Combination Treatment Alone
  Active not recruiting · Phase 2 · Interventional · 29 enrolled · Novartis Pharmaceuticals
  NCT03040973updated 2026-06-11
• A Phase I/II Study of Bexarotene in Combination With ZD1839 (IRESSA®) in the Treatment of Non-Small Cell Lung Cancer
  Completed · Phase 1 · Phase 2 · Interventional · 6 enrolled · Stanford University
  NCT00238628updated 2026-06-04
• Osimertinib Treatment on EGFR T790M Plasma Positive NSCLC Patients (APPLE)
  Completed · Phase 2 · Interventional · 156 enrolled · European Organisation for Research and Treatment of Cancer - EORTC
  NCT02856893updated 2026-06-02
• Clinical Trial of YH25448(Lazertinib) as the First-line Treatment in Patients With EGFR Mutation Positive Locally Advanced or Metastatic NSCLC (LASER301)
  Completed · Phase 3 · Interventional · 393 enrolled · Yuhan Corporation
  NCT04248829updated 2026-05-28
• Bioequivalence Study of Gefitinib Tablets Under Fasting Conditions
  Completed · Phase 1 · Interventional · 38 enrolled · Hunan Kelun Pharmaceutical Co., Ltd.
  NCT03050164updated 2026-05-26
• Bioequivalence Study of Gefitinib Tablets Under Fed Conditions
  Completed · Phase 1 · Interventional · 38 enrolled · Hunan Kelun Pharmaceutical Co., Ltd.
  NCT03050177updated 2026-05-26
• Ningetinib (CT053PTSA) Plus Gefitinib in Stage IIIB or IV NSCLC Patients With EGFR Mutation and T790M Negative
  Completed · Phase 1 · Phase 2 · Interventional · 108 enrolled · Sunshine Lake Pharma Co., Ltd.
  NCT03758287updated 2026-05-12
• Osimertinib and Gefitinib in EGFR Inhibitor naïve Advanced EGFR Mutant Lung Cancer
  Active not recruiting · Phase 1 · Phase 2 · Interventional · 48 enrolled · Dana-Farber Cancer Institute
  NCT03122717updated 2026-04-29
• AZD9291 Versus Gefitinib or Erlotinib in Patients With Locally Advanced or Metastatic Non-small Cell Lung Cancer
  Completed · Phase 3 · Interventional · 674 enrolled · AstraZeneca
  NCT02296125updated 2026-04-21
• Metformin Plus Tyrosine Kinase Inhibitors for Treatment of Patients With Non-small Cell Lung Cancer With EGFR Mutations
  Recruiting · Phase 3 · Interventional · 312 enrolled · Instituto Nacional de Cancerologia de Mexico
  NCT05445791updated 2026-04-09

CPIC-curated drug–gene pairs for Gefitinib. Levels describe the strength of curated evidence and guideline status — never a recommendation to test or to adjust therapy.

• CYP2D6CPIC B/C (provisional)ClinPGx 3FDA label: Actionable PGx

Frequently asked questions

How does Gefitinib work?

The epidermal growth factor receptor (EGFR) is expressed on the cell surface of both normal and cancer cells and plays a role in the processes of cell growth and proliferation. Some EGFR activating mutations (exon 19 deletion or exon 21 point mutation L858R) within NSCLC cells have been identified as contributing to the promotion of tumor cell growth, blocking of apoptosis, increasing the production of angiogenic factors and facilitating the processes of metastasis.

What is Gefitinib used for?

According to FDA labeling, Gefitinib carries indications including: Gefitinib tablets are indicated for the first-line 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 [ see Clinical Studies (14) ]. Limitation of Use: Safety and efficacy of gefitinib tablets have not been established in patients with metastatic NSCLC whose tumors have EGFR mutations other than exon 19 deletions or exon 21 (L858R) substitution mutations [ see Clinical Studies (14) ].. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Gefitinib?

Gefitinib is classified as Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, Kinase Inhibitor, HER1 Antagonists, Protein Kinase Inhibitors, Cellular Synthetic Activity Alteration, Decreased Intercellular Communication, Increased Cellular Death.

What are the brand names for Gefitinib?

Gefitinib is marketed under brand names including Iressa.

What are the contraindications for Gefitinib?

Gefitinib labeling lists contraindications including: None. None.. Always consult the full prescribing information and a clinician.