Osimertinib mesylate

Osimertinib is active against exon 19 deletions, exon 21 mutations, and also the exon 20 T790M mutations. It is preferentially selective for mutated EGFR, and therefore toxicity at therapeutic doses is lower than for first- and second-generation agents. Notably, osimertinib is able to cross the blood-brain barrier, making it active against disease in the CNS.

The collection of ibrutinib (Imbruvica(R), Pharmacyclics Inc.), afatinib, and osimertinib represents the small, yet expanding, group of covalent SMKIs. Ibrutinib is a non-receptor Bruton’s tyrosine kinase inhibitor approved for the treatment of relapsed chronic lymphocytic leukemia. Afatinib, approved for NSCLC in 2013 and squamous NSCLC in 2016, is a second-generation irreversible EGFR inhibitor that targets wild-type EGFR, the mutant T790M EGFR, and HER2. Osimertinib (AZD9291), which was approved by FDA in November 2015, is a third-generation irreversible EGFR inhibitor that selectively targets the mutant T790M EGFR. Rociletinib, which shares a high degree of structural similarity with that of osimertinib, is a promising covalent EGFR inhibitor developed by Clovis Oncology aimed for the treatment of patients with EGFR T790M-mutated NSCLC, until the company terminated its development in May 2016 following a negative vote fromthe FDA’sOncologic Drugs Advisory Committee.

ChEBI: A methanesulfonate (mesylate) salt prepared from equimolar amounts of osimertinib and methanesulfonic acid. Used for treatment of EGFR T790M mutation positive non-small cell lung cancer.

Osimertinib mesylate is approved to treat: Non-small cell lung cancer that has certain EGFR gene mutations. It is used in adults: As adjuvant therapy after surgery to remove the cancer; As the first therapy for cancer that has spread to other parts of the body, or in patients whose cancer has spread to other parts of the body and got worse during or after treatment with another EGFR tyrosine kinase inhibitor.

Tagrisso^TM

Osimertinib toxicity is dose-dependent and is associated with fewer gastrointestinal and dermatologic adverse events than with other approved EGFR TKIs.