AB002. Anlotinib as salvage treatment for patients with relapsed and refractory thymic epithelial tumors

Background Optimal pharmaceutical regimen for advanced thymic epithelial tumors (TETs) remains controversial when first-line chemotherapy fails. This retrospective study aims to evaluate the efficacy and safety of anlotinib treatment for patients with relapsed and refractory TETs. Methods Patients with progression disease after failure of platinum-based chemotherapy were enrolled in this study. Anlotinib was orally taken once a day at an initial dose of 12 mg (10 mg when body weight <60 kg). The cycle was repeated every 3 weeks (2 weeks of treatment followed by 1 week rest). There are 3 dose levels (12, 10 and 8 mg), and dose may be reduced to a lower level when grade 3 toxicity occurred. Objective response rate (ORR) and progression-free survival (PFS) were recorded as primary end points, and they were analyzed separately in thymoma (THY) and thymic carcinoma (TC) cohorts. Meanwhile, toxicities were assessed according to CTCAE (version 5.0). Results There were 50 patients enrolled in this study from October 2018 to June 2021 at a median age of 50 (range, 23–79) years old. Patients with THY and TC were 33 (66%) and 17 (34%) respectively. The ORR in THY and TC patients were 33% (11/33) and 41% (7/17), respectively. The median PFS (mPFS) were 7 (95% CI: 5.9–10.2) months in THY patients and 6 (95% CI: 4.6–9.3) months in TC group. Eleven patients experienced dose reduction due to toxicities, among whom, 8 patients discontinued treatment even after dose reduction. Six patients with THY showed myasthenia gravis (MG) deterioration during treatment, and 2 of them died of MG crisis. Conclusions Anlotinib is active in patients with advanced TETs refractory to routine chemotherapy. Prescription of Anlotinib to patients with MG should be made cautiously.