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Validation of a Lenvatinib Assay: A Pilot Study.
Monica Majumder1, Lucy E Ding1,2, Cameron Wood2
1Department of Endocrinology and Diabetes, Royal North Shore Hospital, Sydney, NSW, Australia.
A new mass spectrometry assay accurately measures lenvatinib levels in thyroid cancer patients. This development is crucial for optimizing treatment and managing adverse events, despite observed variability in drug levels.
Area of Science:
- Oncology
- Pharmacology
- Analytical Chemistry
Background:
- Lenvatinib improves survival in radioiodine-refractory thyroid cancer.
- Treatment-related adverse events (TRAEs) often lead to dose adjustments.
- Accurate monitoring of lenvatinib levels is needed due to lack of validated clinical assays.
Purpose of the Study:
- To develop and validate a mass spectrometry assay for quantifying plasma lenvatinib.
- To assess peak and trough lenvatinib levels in patients with thyroid cancer.
Main Methods:
- A pilot prospective single-center study was conducted.
- High-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) was used for assay development.
- Plasma lenvatinib levels, dosage, TRAEs, and disease progression were recorded.
Main Results:
- A novel LC-MS/MS assay for lenvatinib quantification was successfully developed.
- Trough levels ranged from 4.60 to 30.53 µg/L (median 21.74 µg/L).
- Peak levels varied significantly, with medians of 129.56 µg/L (10mg dose) and 185.23 µg/L (14mg dose).
Conclusions:
- The developed LC-MS/MS assay enables accurate quantification of plasma lenvatinib.
- Significant variability in lenvatinib levels was observed despite consistent dosing.
- Further research is needed to determine the clinical utility of lenvatinib drug monitoring in thyroid cancer.
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