Ositag 80 mg contains Osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) used for the treatment of non-small cell lung cancer (NSCLC) with specific EGFR mutations. Osimertinib selectively inhibits both EGFR-sensitizing mutations and T790M resistance mutations, offering targeted therapy for patients whose tumors have developed resistance to earlier EGFR inhibitors.

রেজিস্টার্ড চিকিৎসকের পরামর্শ অনুযায়ী ঔষধ সেবন করুন

Therapeutic Class

• Tyrosine Kinase Inhibitor (EGFR TKI)

• Antineoplastic Agent

Indications

Ositag 80 mg is indicated for:

• Metastatic NSCLC with EGFR T790M mutation detected by an FDA-approved test in patients who have progressed on or after EGFR TKI therapy.

• First-line treatment of NSCLC with activating EGFR mutations (exon 19 deletions or exon 21 L858R substitution).

• Adjuvant treatment in adult patients with EGFR-mutated NSCLC following complete tumor resection.

Pharmacology / Mode of Action

Osimertinib is a potent, irreversible inhibitor of EGFR, including both sensitizing mutations and the T790M resistance mutation. By covalently binding to the cysteine residue within the ATP-binding site of the EGFR kinase domain, Osimertinib inhibits autophosphorylation and downstream signaling pathways, including RAS/RAF/MEK/ERK and PI3K/AKT, leading to reduced cell proliferation and induction of apoptosis in EGFR-mutant tumor cells.

Osimertinib demonstrates excellent central nervous system (CNS) penetration, making it effective against brain metastases in patients with EGFR-mutated NSCLC.

Dosage and Administration

• The recommended dose is 80 mg orally once daily, with or without food.

• Swallow the tablet whole; do not crush, chew, or split.

• Continue treatment until disease progression or unacceptable toxicity occurs.

• Dose adjustments may be necessary in patients experiencing adverse reactions:

  • 40 mg once daily for moderate toxicity

  • Temporary discontinuation for severe toxicity until recovery, then restart at the same or reduced dose

Side Effects

Common adverse reactions:

• Diarrhea, rash, dry skin, paronychia

• Fatigue, stomatitis, decreased appetite

• Nail disorders and alopecia

Serious adverse reactions:

• Interstitial lung disease (ILD) / pneumonitis

• QT interval prolongation and cardiac arrhythmias

• Cardiomyopathy and heart failure

• Severe dermatologic reactions (e.g., Stevens-Johnson syndrome)

Contraindications

• Hypersensitivity to Osimertinib or any of the excipients in the formulation.

  রেজিস্টার্ড চিকিৎসকের পরামর্শ অনুযায়ী ঔষধ সেবন করুন

Precautions and Warnings

• Monitor pulmonary symptoms; discontinue therapy if ILD is suspected.

• Periodically check electrocardiograms (ECG) for QT prolongation, especially in patients with existing cardiac risk factors.

• Monitor left ventricular ejection fraction (LVEF) during therapy.

• Adjust dose or discontinue for severe hepatic impairment.

• Use caution in patients with renal impairment; no dose adjustment required for mild to moderate renal disease.

Drug Interactions

• Strong CYP3A inducers (e.g., rifampin, phenytoin) may reduce Osimertinib plasma levels.

• Concomitant use with CYP3A inhibitors may increase drug exposure; monitor for toxicity.

Use in Special Populations

• Pregnancy: Category D. Not recommended during pregnancy unless benefits outweigh risks.

• Lactation: Unknown; avoid breastfeeding during treatment.

• Elderly: No dose adjustment required; monitor for tolerability.

Storage Conditions

• Store at 20–25°C, protected from light and moisture.

• Keep out of the reach of children.