From the Guidelines
For patients with aplastic anemia from South East Asia, the recommended initial dose of eltrombopag is 25 mg once daily, as this lower dose minimizes the risk of adverse effects while providing therapeutic benefit due to higher plasma concentrations in Asian patients. This recommendation is based on the understanding that genetic variations in drug metabolism enzymes common in East Asian populations can lead to higher drug exposure at standard doses 1.
Key Considerations
- The initial dose of 25 mg once daily is half the standard starting dose, reflecting the need to adjust for higher plasma eltrombopag concentrations in Asian patients.
- Monitoring platelet counts closely is essential to adjust the dose as needed, typically in 25 mg increments, to achieve and maintain a platelet count ≥50,000/µL.
- The maximum dose should not exceed 150 mg daily to prevent excessive drug exposure and potential adverse effects.
- Regular blood tests are crucial to monitor platelet response and adjust treatment accordingly, ensuring the balance between therapeutic efficacy and safety.
Clinical Context
In the management of aplastic anemia, especially in patients from South East Asia, it's critical to consider the pharmacogenomics of eltrombopag to optimize dosing and minimize toxicity. While the provided guidelines primarily focus on the management of immune-related adverse events and transitioning patients with immune thrombocytopenia to second-line therapy, the principle of adjusting doses based on ethnic differences in drug metabolism applies to the use of eltrombopag in aplastic anemia as well 1.
Dosing Adjustments
Dosing adjustments should be made cautiously, avoiding abrupt interruptions or excessive dose changes, which can lead to platelet fluctuations. The goal is to use the minimum effective dose necessary to maintain a target platelet count and prevent bleeding, considering the individual patient's response and tolerance to eltrombopag.
From the Research
Initial Dose of Eltrombopag in Aplastic Anemia
The initial dose of eltrombopag in aplastic anemia can vary depending on the patient population and the specific study.
- In a study of Japanese patients with aplastic anemia refractory or intolerant to immunosuppressive therapy, the initial dose of eltrombopag was 25 mg once daily, with a dose-escalation fashion (25,50,75, or 100 mg once daily) depending on individual platelet responses 2.
- In a real-world experience study, the median maximum dose of eltrombopag was 150 mg/day, with a range of 50-300 mg/day 3.
- In a phase 2 study, the initial dose of eltrombopag was 50 mg, which could be increased to a maximum dose of 150 mg daily 4.
- In a study of Chinese patients with relapsed/refractory aplastic anemia, the dosage of eltrombopag varied from 25 mg every other day to 100 mg every day, with a median dose of 75 mg qd 5.
- In a nationwide survey of French patients with severe aplastic anemia, the median daily dose of eltrombopag was 150 mg 6.
Dose in South East Asian Patients
Specifically, for patients from South East Asia, the initial dose of eltrombopag in aplastic anemia is not explicitly stated in the provided studies. However, based on the study of Japanese patients, which may be relevant to the South East Asian population, the initial dose of 25 mg once daily may be considered 2.
Key Points
- The initial dose of eltrombopag in aplastic anemia can vary depending on the patient population and the specific study.
- The dose of eltrombopag may need to be adjusted based on individual patient responses.
- Further studies are needed to determine the optimal initial dose of eltrombopag in South East Asian patients with aplastic anemia.