Osimertinib

Indications

Osimertinib is used for: Non-small Cell Lung Cancer Indicated for the treatment of patients with metastatic epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer (NSCLC)

Adult Dose

Non-small Cell Lung Cancer 80 mg once daily. Hepatic impairment Mild (TB

Child Dose

Renal Dose

Administration

May be taken with or without food: Take at the same time each day. Swallow whole, do not crush/split/chew. For patients w/ swallowing difficulties, tab may be dispersed in 50 mL non-carbonated water & stir w/o crushing until dispersed. Drink immediately. Rinse glass w/ another ½ glass of water & drink. Dispersed liqd may also be administered via nasogastric tube by using 15 mL for initial dispersion & 15 mL for residue rinses. The tube should be flushed w/ water after administration. Soln should be administered w/in 30 min of the addition of tab to water.

Contra Indications

Precautions

Determine EGFR T790M mutation status prior to treatment. Interstitial lung disease (eg, pneumonitis). Avoid use in patients w/ congenital long QT syndrome. Severe & end-stage renal impairment. May affect ability to drive or operate machinery. Women of childbearing potential not using contraception. Use effective contraception for at least 6 wk for females & 4 mth for males. Not recommended during pregnancy. Lactation. Based on its mechanism of action and animal data, Osimertinib can cause fetal harm when administered to a pregnant woman. There are no available data on Osimertinib use in pregnant women. Pregnant women should be advised of the potential risk to a fetus. There are no data on the presence of Osimertinib in human milk, the effects of Osimertinib on the breastfed infant or on milk production. Lactating woman should be advised not to breastfeed during treatment.

Pregnancy-Lactation

Interactions

Decreased exposure w/ strong CYP3A4 inducers (eg, phenytoin, rifampicin, carbamazepine, St. John's wort). May increase AUC & Cmax of rosuvastatin. May increase the exposure of BCRP substrates. Decreased AUC & Cmax of simvastatin.

Adverse Effects

Side effects of Osimertinib : >10% Lymphopenia (63%),Thrombocytopenia (54%),Anemia (44%),Diarrhea (42%),Rash (41%),Neutropenia (33%),Dry skin (31%),Hyponatremia (26%),Nail toxicity (25%),ypermagnesemia (20%),Eye disorders (18%),Nausea (17%),Decreased appetite (16%),Constipation (15%),Pruritus (14%),Fatigue (14%),Cough (14%),Back pain (13%),Stomatitis (12%) 1-10% Headache (10%),Venous thromboembolism (7%),Pneumonia (4%),Interstitial lung disease/pneumonitis (3.3%),QTc increased from baseline >60 msec (2.7%),Cardiomyopathy (1.4%) <1% Keratitis

Mechanism of Action

Osimertinib is kinase inhibitor of the epidermal growth factor receptor (EGFR), which binds irreversibly to certain mutant forms of EGFR (T790M, L858R, and exon 19 deletion) at approximately 9-fold lower concentrations than wild-type. In cultured cells and animal tumor implantation models, osimertinib exhibited anti-tumor activity against non-small cell lung cancer (NSCLC) lines harboring EGFR-mutations (T790M/L858R, L858R, T790M/exon 19 deletion, and exon 19 deletion) and, to a lesser extent, wild-type EGFR amplifications.