Osikin Tablet | Osimertinib 80 mg

Indications :

Osikin is indicated for the treatment of patients with metastatic EGFR T790M mutation-positive NSCLC, as detected by an FDA-approved test, whose disease has progressed on or after EGFR tyrosine kinase inhibitor (TKI) therapy. Osikin 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 mutations, as detected by an FDA-approved test.

Pharmacology :

In cultured cells and animal tumor implantation models, Osimertinib exhibited anti-tumor activity against 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. 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, Osimertinib also inhibited the activity of HER2, HER3, HER4, ACK1, and BLK at clinically relevant concentrations. 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.

The area under the plasma concentration-time curve (AUC) and maximal plasma concentration (C max ) of Osimertinib increased dose proportionally over 20 to 240 mg dose range (i.e., 0.25 to 3 times the recommended dosage) after oral administration and exhibited linear pharmacokinetics (PK). Administration of Osimertinib orally once daily resulted in approximately 3-fold accumulation withsteady state exposures achieved after 15 days of dosing. At steady state, the C max to C min (minimal concentration) ratio was 1.6-fold.

Absorption: The median time to C max of Osimertinib was 6 hours (range 3-24 hours). Following administration of a 20 mg Osimertinib tablets with a high-fat, high-calorie meal (containing approximately 58 grams of fat and 1000 calories), the C max and AUC of Osimertinib were compared to that under fasting conditions.

Distribution: The mean volume of distribution at steady-state (Vss/F) of Osimertinib was 986 L. Plasma protein binding of Osimertinib was 95%.

Elimination: Osimertinib plasma concentrations decreased with time and a population estimated mean half-life of Osimertinib was 48 hours, and oral clearance (CL/F) was 14.2 (L/h).

Metabolism: The main metabolic pathways of Osimertinib were oxidation (predominantly CYP3A) and dealkylation in vitro. Two pharmacologically active metabolites (AZ7550 and AZ5104) have been identified in the plasma after Osimertinib oral administration. The geometric mean exposure (AUC) of each metabolite (AZ5104 and AZ7550) was approximately 10% of the exposure of Osimertinib at steady-state.

Excretion: Osimertinib is primarily eliminated in the feces (68%) and to a lesser extent in the urine (14%). Unchanged Osimertinib accounted for approximately 2% of the elimination.

Dosage & Administration :

The recommended dose of Osimertinib is 80 mg tablet once a day until disease progression or unacceptable toxicity. Osimertinib can be taken with or without food. If a dose of Osimertinib is missed, do not make up the missed dose and take the next dose as scheduled. Disperse tablet in 60 ml (2 ounces) of non-carbonated water only. Stir until tablet is dispersed into small pieces (the tablet will not completely dissolve) and swallow immediately. Do not crush, heat, or ultrasonicate during preparation. Rinse the container with 120 ml to 240 ml (4 to 8 ounces) of water and immediately drink. If administration via nasogastric tube is required, disperse the tablet as above in 15 ml of non-carbonated water, and then use an additional 15 ml of water to transfer any residues to the syringe. The resulting 30 ml liquid should be administered as per the nasogastric tube instructions with appropriate water flushes (approximately 30 ml).