Iressa
An oral targeted therapy used to treat EGFR-mutated non-small cell lung cancer.
Where Gefitinib is approved
All regulators →Of the three regulators tracked here, the first to approve Gefitinib was the US, on 5 May 2003. It is approved in 3 of the 3 regulators tracked here.
From the regulators' own registers: FDA Drugs@FDA, the EMA medicines list and Health Canada's Notice of Compliance database. Dates are the first listed approval of a product containing only this substance; combination products and nationally authorised EU medicines are not counted.
What health systems spend on Gefitinib
All medicines →From NHSBSA Prescription Cost Analysis (Open Government Licence v3.0) and CMS State Drug Utilization Data. Both are gross amounts: neither system publishes its discounts or rebates per drug. Products combining several substances are not counted here.
How Gefitinib works
All drug targets →- Epidermal growth factor receptor erbB1 inhibitor InhibitorTarget: EGFR epidermal growth factor receptor✓ In ChEMBL and the Guide to Pharmacology
- AdenocarcinomaPhase 3
- Bladder transitional cell carcinomaPhase 3
- Head and neck cancerPhase 3
- Lung adenocarcinomaPhase 3
- Non-small cell squamous lung carcinomaPhase 3
- Colorectal carcinomaPhase 2/3
- FeverPhase 2
- Acute myeloid leukemiaPhase 2
- Breast cancerPhase 2
- Breast carcinomaPhase 2
Mechanisms and diseases from ChEMBL via the Open Targets Platform (release 26.09), ChEMBL record CHEMBL939, CC BY-SA 3.0. Targets checked against the IUPHAR/BPS Guide to PHARMACOLOGY (2026.3), ligand 4941, CC BY-SA 4.0. Trial phases are not approvals: approved uses are shown from the regulators' own records where we hold them.
NICE appraisals of Gefitinib
All NICE appraisals →NICE, which decides whether the NHS in England should fund new medicines, has published 3 technology appraisals of Gefitinib. 3 are current, and 2 of these recommend it for at least some patients.
| Appraisal | NICE recommendation | Published | Status |
|---|---|---|---|
| Erlotinib and gefitinib for treating non-small-cell lung cancer that has progressed after prior chemotherapy NICE TA374 | Optimised Not recommended | 16 Dec 2015 | Current |
| Gefitinib for the first-line treatment of locally advanced or metastatic non-small-cell lung cancer NICE TA192 | Recommended | 28 Jul 2010 | Current |
| Gefitinib for the second-line treatment of locally advanced or metastatic non-small-cell lung cancer (terminated appraisal) NICE TA175 | Terminated (no company submission) | 22 Jul 2009 | Current |
NICE decisions apply to the NHS in England. In Ireland the HSE decides on reimbursement, advised by the National Centre for Pharmacoeconomics. Titles, categories and dates link to the guidance on nice.org.uk. © NICE 2026 technology appraisal guidance. Available from www.nice.org.uk/guidance. All rights reserved. Subject to Notice of rights. NICE guidance is prepared for the National Health Service in England. All NICE guidance is subject to regular review and may be updated or withdrawn. NICE accepts no responsibility for the use of its content in this product/publication.
Patient leaflets for Gefitinib
The package leaflet is the official guide for patients that comes with every medicine. These links go to the regulators that publish it.
- IEIreland: 1 product on the HPRA listEach product record links to the HPRA, which publishes the leaflet and SmPC.
- EUEuropean Union: IressaEMA product information: package leaflet and summary of product characteristics in every EU language.
- UKUnited Kingdom: Search MHRA ProductsPatient information leaflets and SmPCs for UK-licensed products.
- USUnited States: Search DailyMedFDA-approved labels, including patient and medication guides.
Leaflets differ between brands and countries; always read the one that comes with your own medicine. This is regulatory information, not medical advice.
Reference identifiers for Gefitinib
- ATC code
- L01XE02
- ChEMBL
- CHEMBL939
- DrugBank
- DB00317
- PubChem CID
- 123631
- CAS number
- 184475-35-2
- FDA UNII
- S65743JHBS
- Wikidata
- Q417824
- Wikipedia
- Gefitinib
Codes that identify this medicine in other databases, from Wikidata (CC0), matched by its ChEMBL ID. The ATC code is the WHO classification of what the medicine is used for.
What Iressa is used for
IRESSA is 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 IRESSA 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) ] . IRESSA is a tyrosine kinase inhibitor 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. (1) Limitation of Use: Safety and efficacy of IRESSA have not b…
How it works
12.1 Mechanism of Action 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 reversibly inhibits the kinase activity of wild-type and certain activating mutations of EGFR, preventing autophosphorylation of tyrosine residues associated with the receptor, thereby inhibiti…
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How this page is built
The facts on this page are pulled directly from official U.S. FDA datasets — they are not written from memory. Each field below names the dataset it came from, so you can check it yourself.
- FDA Drug Label (openFDA) ↗ Indications, mechanism of action and pharmacologic class
- Drugs@FDA ↗ First FDA approval date and the company holding the application
- FDA Drug Shortage Database ↗ Current US supply / shortage status
Plain-English summaries and drug-class explainers are written and reviewed by Sreepriya Prasannan (MSc Digital Transformation of Life Sciences (Innopharma Education / Griffith College); MSc & BSc Botany). Data is retrieved automatically from the sources above and cross-checked with AI-assisted verification (Anthropic's Claude) — brand and generic names are matched against the exact FDA product record so that a combination product or a different formulation cannot be mistaken for the drug on this page. An editor reviews the result before publication. We describe this in full in our editorial standards and corrections policy. The FDA data on this page was last retrieved on 11 Oct 2026. How every register is built: methodology · fixes we have made: corrections log.