Biomarkers for predicting and assessing responsiveness of thyroid and kidney cancer subjects to lenvatinib compounds

A method for treating differentiated thyroid cancer, comprising:

• providing a first blood sample obtained, before initiation of a therapy comprising lenvatinib or a pharmaceutically acceptable salt thereof, from a human subject having or suspected of having a differentiated thyroid cancer;
• providing a second blood sample obtained from the human subject after initiation of the therapy comprising lenvatinib or a pharmaceutically acceptable salt thereof;
• measuring the concentration of thyroglobulin in the first blood sample and the second blood sample, wherein the ratio of the concentrations of thyroglobulin in the blood samples (second blood sample/first blood sample) is reduced as compared to a control, wherein the control is a pre-established reference ratio established by an analysis of thyroglobulin expression pre- and post-treatment with lenvatinib or a pharmaceutically acceptable salt thereof in one or more subjects that have not responded to treatment with lenvatinib or a pharmaceutically acceptable salt thereof;
• and
• further administering lenvatinib or a pharmaceutically acceptable salt thereof to the human subject, wherein the human subject has a ratio of the concentrations of thyroglobulin in the blood samples (second blood sample/first blood sample) that is reduced as compared to the control.