Eltrombopag for Thrombocytopenia: Recommended Use and Dosage
Eltrombopag is recommended as an effective thrombopoietin receptor agonist for patients with persistent or chronic immune thrombocytopenia (ITP) who have failed first-line therapies, with a starting dose of 50 mg once daily for adults, adjusting based on platelet response and patient characteristics. 1, 2
Indications and Patient Selection
- Eltrombopag is indicated for patients with persistent or chronic ITP who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy 1
- It can be used in both splenectomized and non-splenectomized patients, with response rates of 79% and 88% respectively 1
- Patients should have platelet counts <30 × 10^9/L or be experiencing bleeding symptoms requiring treatment 2
- Eltrombopag can also be used for thrombocytopenia in patients with chronic liver disease undergoing invasive procedures, though with caution due to increased risk of portal vein thrombosis 3, 1
Dosing Recommendations
Initial Dosing:
- Standard starting dose: 50 mg once daily for most adult patients 2
- Reduced initial dose of 25 mg daily for patients with:
Dose Adjustments:
- Adjust dose to achieve and maintain platelet count ≥50 × 10^9/L to reduce bleeding risk 2
- Increase dose to 75 mg daily if needed after 2-3 weeks if initial response is insufficient 2, 4
- Maximum dose should not exceed 75 mg daily 1, 2
- For patients achieving stable response (platelet count ≥50 × 10^9/L for at least 6 months), consider tapering by reducing dose by 25 mg every 2 weeks 1
Monitoring and Response:
- Platelet count response typically occurs within 1-2 weeks of starting treatment 2, 4
- By day 15, more than 80% of patients receiving 50-75 mg daily show response 1
- Monitor platelet counts weekly until stable, then monthly 2
- Discontinue if platelet count exceeds 200 × 10^9/L 2
- Discontinue if no response after 4 weeks at maximum dose of 75 mg daily 2
Safety Considerations and Adverse Effects
- Most common adverse events: headache (≥20% of patients) 1
- Serious potential adverse events include:
- Patients with chronic liver disease have increased risk of portal vein thrombosis 3
- Monitor liver function tests regularly during treatment 2
Special Populations
- Hepatic Impairment: Reduce initial dose to 25 mg daily 2
- East/Southeast-Asian Patients: Reduce initial dose to 25 mg daily 2
- Elderly Patients: No specific dose adjustments required based on age alone 2
- Pregnancy: Use with caution as eltrombopag may cause fetal harm based on animal studies 2
- Breastfeeding: Not recommended during treatment due to potential risks 2
Duration of Treatment
- Eltrombopag typically requires continuous administration to maintain platelet response 1
- Sustained response has been documented for up to 1.5 years with continuous administration 1
- When discontinuing, taper slowly to avoid rebound thrombocytopenia 1
- For patients with stable response for ≥6 months, consider tapering by reducing eltrombopag by 25 mg every 2 weeks 1
Treatment Algorithm
Initial Assessment:
- Confirm diagnosis of persistent/chronic ITP or other approved indication
- Verify platelet count <30 × 10^9/L or clinically significant bleeding
- Assess liver function and ethnicity for initial dosing
Initial Treatment:
- Start with 50 mg once daily (25 mg for patients with hepatic impairment or East/Southeast-Asian ancestry)
- Monitor platelet counts weekly initially
Dose Adjustment:
- If platelet count remains <50 × 10^9/L after 2-3 weeks, increase to 75 mg daily
- If platelet count >200 × 10^9/L, stop treatment and resume at lower dose when <150 × 10^9/L
- If platelet count 50-200 × 10^9/L, maintain current dose
Long-term Management:
- Once stable, monitor platelet counts monthly
- For patients with stable response for ≥6 months, consider gradual tapering
- Continue indefinitely for patients who require ongoing treatment