Long-term follow-up and exploratory analysis of lenvatinib in patients with metastatic or recurrent thymic carcinoma: Results from the multicenter, phase 2 REMORA trial

Objectives The main objective of this report was to detail the long-term follow-up data from the REMORA study, which investigated the safety and efficacy of lenvatinib in patients with thymic carcinoma. In addition, an exploratory analysis of the association between relative dose intensity (RDI) and the efficacy of lenvatinib is presented. Materials and Methods The single-arm, open-label, phase 2 REMORA study was conducted at eight Japanese institutions. Forty-two patients received oral lenvatinib 24 mg once daily in 4-week cycles until the occurrence of intolerable adverse events or disease progression. The REMORA long-term follow-up data were evaluated, including overall survival (OS). RDI was calculated by dividing the actual dose administered to the patient by the standard recommended dose. This trial is registered on JMACCT (JMA-IIA00285) and on UMIN-CTR (UMIN000026777). Results The updated median OS was 28.3 months (95 % confidence interval [CI]: 17.1–34.0 months), and the OS rate at 36 months was 35.7 % (95 % CI: 21.7 %–49.9 %). When grouped by RDI of lenvatinib, the median OS was 38.5 months (95 % CI: 31.2–not estimable) in patients with ≥ 75 % RDI and 17.3 months (95 % CI: 13.4–26.2 months) in patients with < 75 % RDI (hazard ratio 0.46 [95 % CI: 0.22–0.98]; P = 0.0406) at 8 weeks. Patients who maintained their lenvatinib dose over 8 weeks had a higher objective response rate than patients whose doses were reduced (75.0 % vs 29.4 %; P = 0.0379). No new safety concerns or treatment-related deaths were reported, and lenvatinib had a tolerable safety profile. Conclusion This follow-up report updated OS in patients with metastatic or recurrent thymic carcinoma. A higher RDI of lenvatinib at 8 weeks could be associated with improved outcomes.