The FDA has approved Eisai's Lenvima (lenvatinib mesylate) for the treatment of locally recurrent or metastatic, progressive, radioactive iodine-refractory differentiated thyroid cancer (RAI-R DTC). Lenvatinib inhibits multiple growth factor receptor tyrosine kinases.
The approval was based on data from the phase III trial SELECT (Study of [E7080] LEnvatinib in Differentiated Cancer of the Thyroid; ClinicalTrials.gov Identifier NCT01321554), which achieved its primary endpoint of progression-free survival (PFS) improvement for oral lenvatinib 24 mg once daily compared to placebo in patients with radioiodine-refractory differentiated thyroid cancer. PFS was 18.3 and 3.6 months for lenvatinib and placebo, respectively. Tumor shrinkage was observed in 65% of the lenvatinib group compared to 2% of the placebo group.
On disease progression, placebo-treated patients became eligible to receive lenvatinib. Treatment-related adverse events occurred in over 40% of the lenvatinib group. The most common were hypertension (67.8%), diarrhea (59.4%), fatigue or asthenia (59.0%), decreased appetite (50.2%), weight loss (46.4%) and nausea (41.0%). Lenvatinib is under regulatory review in the E.U., Japan, Switzerland, South Korea, Canada, Singapore, Russia, Australia and Brazil. Eisai is also developing the drug for the treatment of hepatocellular carcinoma, renal cell carcinoma and non-small cell lung cancer (NSCLC) (Eisai News Release; FDA News Release).