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Tagrisso vs Iressa

Osimertinib  ·  Gefitinib

Both are EGFR inhibitors. Here is how Tagrisso and Iressa compare on class, mechanism, dosing, approval and supply.

At a glance

TagrissoOsimertinib
IressaGefitinib
Brand name
Tagrisso
Iressa
Drug class
EGFR inhibitor
EGFR inhibitor
Route
Oral
Oral
Marketed by
AstraZeneca
AstraZeneca
First FDA approval
13 Nov 2015
5 May 2003
US shortage
Not listed
Not listed

Key differences

What each one treats

TagrissoOsimertinib

TAGRISSO is a kinase inhibitor indicated for: • adjuvant therapy after tumor resection in adult patients with non-small cell lung cancer (NSCLC) whose tumors have epidermal growth factor receptor (EGFR) exon 19 deletions or exon 21 L858R mutations, as detected by an FDA-approved test. ( 1.1 , 2.2 ) • the treatment of adult patients with locally advanced, unresectable (stage III) NSCLC whose disease has not progressed during or following concurrent or sequential platinum-based chemoradiation therapy and whose tumors have EGFR exon 19 deletions or exon 21 L858R mutations, as detected by an FDA-approved test. ( 1.2 , 2.2 ) • the first-line treatment of adult patients with metastatic NSCLC whose tumors have EGFR exon 19 deletions or exon 21 L858R mutations, as detected by an FDA-approved test. ( 1.3 , 2.2 ) • in combination with pemetrexed and platinum-based chemotherapy, the first-line tre…

IressaGefitinib

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 each one works

TagrissoEGFR inhibitor

12.1 Mechanism of Action Osimertinib is a kinase inhibitor of the epidermal growth factor receptor (EGFR), which binds irreversibly to certain mutant forms of EGFR (T790M, L858R, and exon 19 deletions) at approximately 9-fold lower concentrations than wild-type. Two pharmacologically-active metabolites (AZ7550 and AZ5104 circulating at approximately 10% of the parent) with similar inhibitory profiles to osimertinib have been identified in the plasma after oral administration of osimertinib. AZ7550 showed a similar potency to osimertinib, while AZ5104 showed greater potency against exon 19 deletion and T790M mutants (approximately 8-fold) and wild-type (approximately 15-fold) EGFR. In vitro …

IressaEGFR inhibitor

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…

Related comparisons

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Read more

Tagrisso profile Iressa profile EGFR Inhibitors All comparisons
This is not medical advice, and not a recommendation of one drug over the other.

Which medicine is right for a given person depends on their diagnosis, other conditions, other medicines, kidney and liver function, pregnancy, and cost or reimbursement — none of which this page knows. Two drugs in the same class are not automatically interchangeable. Never start, stop or switch a prescription medicine on the basis of a web page; that decision belongs to you and your clinician or pharmacist.

Class and summary text is written by the Priya Life Science editorial team. Label, mechanism, route, manufacturer and approval data come from the U.S. FDA via the openFDA API; shortage status from the FDA Drug Shortage Database. Approvals, indications and brand names differ between the US, EU/Ireland (EMA/HPRA) and other regions — a drug approved in one may not be approved, or may carry a different name, in another.