Phase I evaluation of lenvatinib and weekly paclitaxel in patients with recurrent endometrial, ovarian, fallopian tube, or primary peritoneal Cancer

Objectives To estimate the maximally tolerated dose (MTD) and describe toxicities associated with lenvatinib and weekly paclitaxel in patients with recurrent endometrial and platinum resistant epithelial ovarian cancer. Methods Using a 3 + 3 design patients were given weekly paclitaxel 80 mg/m2 IV day 1, 8, 15 and oral levantinib daily on a 28-day cycle. Lenvatinib dose levels were 8 mg, 12 mg, 16 mg, 20 mg. Toxicities were recorded using CTCAE v4.03 and response was determined with imaging after cycle 2, then every 3rd cycle, using RECIST 1.1 criteria. Results 26 patients were enrolled; 19 with ovarian cancer (14 high grade serous, 1 low grade serous, 2 clear cell, 1 endometrioid, and 1 carcinosarcoma), and 7 with endometrial cancer (3 serous, and 4 endometrioid). The MTD was established at lenvatinib 16 mg and weekly paclitaxel 80 mg/m2. Toxicities (all grades) occurring in ≥25% of patients included anemia, neutropenia, lymphopenia, mucositis, nausea, diarrhea, anorexia, hypertension, fatigue, proteinuria, epistaxis, hoarseness. Twenty-three patients were evaluable for response and PFS; 15 (65%) had a partial response, 7 (30%) stable, 1 (4%) progressive disease with an objective response rate of 65%; 71% in ovarian and 50% in endometrial cancer. Median progression free survival (PFS) is 12.4 months; 14.0 months in endometrial cancer, 7.2 months in ovarian cancer; 54% had a PFS > 6 months. The median duration of response for PR patients (n = 15) was 10.9 months. Conclusions The regimen was tolerable with manageable side effects. Encouraging activity was observed in endometrial and ovarian cancer, and warrants further development.