Osimertinib: Brands, Price & Uses in Bangladesh

Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) indicated for the treatment of non-small cell lung cancer (NSCLC) in patients whose tumors have specific EGFR mutations. Indications are classified below by strength of evidence and setting.

Established / FDA-Approved Indications

• First-line treatment of metastatic NSCLC: As monotherapy in adult patients with metastatic NSCLC whose tumors have EGFR exon 19 deletions or exon 21 L858R mutations, as detected by an approved test.
• First-line combination therapy: In combination with pemetrexed and platinum-based chemotherapy for first-line treatment of the same EGFR exon 19 deletion or exon 21 L858R metastatic NSCLC population (combination therapy required for this indication; not for use as monotherapy in this specific regimen).
• Adjuvant treatment: Following tumor resection in adult patients with early-stage (Stage IB-IIIA) EGFR exon 19 deletion or exon 21 L858R mutation-positive NSCLC.
• Locally advanced, unresectable (Stage III) NSCLC: In patients with EGFR exon 19 deletion or exon 21 L858R mutation-positive disease whose disease has not progressed during or following platinum-based chemoradiation therapy.
• Second-line, mutation-specific treatment: Treatment of metastatic EGFR T790M mutation-positive NSCLC, as detected by an approved test, in patients whose disease has progressed on or after prior EGFR TKI therapy.

All indications require confirmed, specific EGFR mutation status (exon 19 deletion, exon 21 L858R, or T790M as applicable) prior to starting treatment; Osimertinib is a biomarker-directed therapy and is not appropriate for EGFR-mutation-negative or untested NSCLC.

General Dosing

The recommended dose of Osimertinib is 80 mg orally once daily, with or without food, taken at approximately the same time each day, until disease progression or unacceptable toxicity (see Duration of Treatment for setting-specific durations).

Dose Modifications

Dose reduction to 40 mg once daily may be required for certain adverse reactions such as QTc prolongation, interstitial lung disease follow-up management, or other significant toxicity, per physician assessment. If concomitant use of a strong CYP3A4 inducer cannot be avoided, the dose may be increased to 160 mg once daily under close physician supervision (see Interactions).

Renal and Hepatic Impairment

No dose adjustment is required in patients with mild to moderate renal or hepatic impairment. Data in severe renal or hepatic impairment are limited; use with caution and close monitoring in these patients.

Missed Dose

If a dose of Osimertinib is missed by more than 12 hours, the missed dose should be skipped and the next dose taken at the usual scheduled time.

Very Common

• Diarrhea
• Rash and dry skin
• Nail toxicity (including paronychia)
• Stomatitis (mouth ulcers/inflammation)
• Fatigue
• Musculoskeletal pain
• Laboratory abnormalities: reduced white blood cell count (leukopenia, lymphopenia, neutropenia), low platelet count (thrombocytopenia), anemia

Serious Adverse Effects (Require Prompt Medical Attention)

• Interstitial lung disease (ILD)/pneumonitis: Can be severe and, in rare cases, fatal. Seek prompt evaluation for any new or worsening respiratory symptoms such as shortness of breath, cough, or fever.
• QT interval prolongation: May increase risk of abnormal heart rhythms; symptoms such as palpitations, dizziness, or fainting should be reported immediately.
• Cardiomyopathy/reduced heart pumping function (reduced ejection fraction): May present as shortness of breath, swelling of legs/ankles, or fatigue.
• Keratitis (eye inflammation): May present as eye pain, redness, light sensitivity, blurred vision, or excessive tearing; requires prompt ophthalmology referral.