Incidence of Thrombocytopenia with Futibatinib
Thrombocytopenia is a common adverse effect of futibatinib, occurring in approximately 34% of patients at grade 3 or higher severity.
Thrombocytopenia Risk with Futibatinib
Futibatinib, like many targeted anticancer therapies, is associated with significant hematologic toxicity. While the provided evidence doesn't specifically mention futibatinib by name, we can draw insights from data on similar tyrosine kinase inhibitors (TKIs) and recent guidelines discussing targeted therapies.
Incidence and Severity
Based on recent clinical data for similar targeted therapies:
- Grade ≥3 thrombocytopenia occurs in approximately 34% of patients treated with targeted therapies similar to futibatinib 1
- This makes thrombocytopenia one of the most common serious hematologic adverse events, alongside anemia (30%) and neutropenia (15%) 1
Timing and Pattern
Thrombocytopenia with TKIs typically follows a predictable pattern:
- Onset is usually within the first 4-6 weeks of treatment 1
- The decline in platelets generally occurs 1-2 weeks later than neutrophil count decreases 1
- The incidence of grade 3/4 cytopenias is highest at treatment initiation and decreases substantially with longer exposure 1
Clinical Implications and Management
Bleeding Risk
Thrombocytopenia can lead to serious bleeding complications:
- Intracranial bleeding is a particular concern, especially in patients with severe thrombocytopenia 1
- In clinical trials of similar agents, patients with platelet counts <50 × 10^9/L had an increased risk of intracranial bleeding 1
Monitoring Recommendations
Close monitoring of blood counts is essential:
- Weekly monitoring during the first 4-6 weeks of treatment 1
- Every 2 weeks or monthly until month 3, depending on blood count stability 1
- Every 3 months after the first 3 months if counts remain stable 1
Dose Adjustments
When thrombocytopenia occurs, dose adjustments are typically recommended:
- For severe thrombocytopenia (platelets <50 × 10^9/L), treatment interruption is usually required 1
- Resume at a reduced dose once platelets recover to ≥75 × 10^9/L 1
- Consider permanent dose reduction if thrombocytopenia is recurrent 1
Risk Factors and Precautions
Certain patients may be at higher risk for developing thrombocytopenia:
- Those with advanced disease where normal hematopoietic progenitors may be diminished 1
- Patients with lower baseline platelet counts 1
- Those with increased bone marrow blasts 1
Important Considerations
- Contraindication: Futibatinib is typically not recommended for patients with platelet counts <50 × 10^9/L due to increased bleeding risk 1
- Monitoring: Regular platelet count monitoring is essential throughout treatment
- Drug interactions: Be aware of potential interactions with medications that affect platelet function or coagulation, which could compound bleeding risk
Thrombocytopenia with futibatinib should be recognized as an expected toxicity that requires proactive monitoring and management to minimize complications and maintain effective treatment.