Dosing, Monitoring, and Counseling: The Pharmacist's Role in TKI Therapy for Systemic Mastocytosis

In this episode, "Dosing, Monitoring, and Counseling: The Pharmacist's Role in TKI Therapy for Systemic Mastocytosis," the expert pharmacists explored the following questions:

How can pharmacists aid in the different dosing requirements for novel tyrosine kinase inhibitors such as avapritinib?

How does it differ in the indolent vs. advanced setting?

What is the role of the pharmacist in monitoring and managing the adverse events, as well as drug-drug interactions, associated with tyrosine kinase inhibitors?

What are the main patient education points for patients who are receiving tyrosine kinase inhibitors for systemic mastocytosis?

The panelists examined dosing considerations for avapritinib, starting at 25 mg with titration to 50 mg in indolent systemic mastocytosis (SM) compared with 200 mg in advanced disease, as well as midostaurin's 100 mg twice-daily dosing in advanced SM, emphasizing patient counseling that dose adjustments reflect tolerability rather than treatment failure. Lewis-Gonzalez detailed the pharmacist's role in monitoring adverse events such as thrombocytopenia, gastrointestinal toxicity, and hepatic or cardiac effects, alongside managing CYP3A4-mediated drug interactions through thorough medication reconciliation, including over-the-counter supplements. Smith outlined key patient education points, including taking avapritinib on an empty stomach, continuing antihistamine therapy alongside TKI treatment, recognizing warning signs of intracranial hemorrhage, and monitoring for cognitive effects and periorbital edema during therapy.

Throughout the conversation, the experts provided a comprehensive reflection on the field and the factors that may shape how clinicians approach care moving forward.

The next episode in this series, "Total Symptom Score and Dose Adjustments: Fine-Tuning TKI Therapy in Systemic Mastocytosis," features the panelists advancing their conversation on systemic mastocytosis and focusing on how pharmacists integrate the Total Symptom Score into clinical practice, distinguish drug-related from disease-related adverse effects, and apply best practices for dose reductions and treatment holidays.