A phase II study of sunitinib in recurrent or metastatic endometrial carcinoma: A trial of the PMH Phase II Consortium

5576 Background: Endometrial cancer (EC) is the most common gynecologic malignancy. Vascular endothelial growth factor (VEGF) overexpression in EC correlates with poor outcome, thus targeting VEGF is a rational therapeutic approach. We have conducted a two-stage open-label phase II study in advanced EC with sunitinib, an oral tyrosine kinase inhibitor of multiple VEGF receptors. Methods: Eligible pts have recurrent or metastatic EC and have received up to 1 prior chemotherapy (CT) regimen for metastatic disease. Sunitinib is given at 50 mg daily (OD) for 4 consecutive weeks (wks) followed by 2 wks off. Dose could be reduced to 37.5 mg OD and then 25 mg OD in the setting of toxicity. Imaging is repeated every 12 wks. Primary objectives are objective response rate (ORR by RECIST) and rate of 6-month progression-free survival (PFS). If 1 or more responses occur in the first 15 evaluable pts, the study would continue to a second stage (total = 30 pts). Secondary objectives are time to progression (TTP), overall survival (OS), and safety. Results: We report the results of the first stage of this study. Sixteen pts have been treated (median age: 63; range 41–74) with 37 cycles of sunitinib (median 2; range: 1–7). Baseline ECOG PS was 0 (7 pts), 1 (8 pts), or 2 (1 pt). Histology was endometrioid (7 pts), serous (5 pts), clear cell (1 pt), or mixed/other (3 pts). Most pts had high-grade histology (G3: 8; G2: 4; G1: 2; GX: 2). Nine pts had prior adjuvant CT, 8 pts had 1 prior CT for advanced EC, 4 pts had prior hormones and 7 pts had prior radiotherapy. Partial response was achieved by 2 pts (ORR = 12.5%), and 2 other pts had a best response of stable disease; 3 of these pts remained progression-free > 6 months. Median TTP = 2.5 months (95% CI: 2.47-NR), and median OS = 6.2 months (95% CI: 5.1-NR). Grade 3/4 adverse events (AE) in >10% of pts were fatigue (7 pts, 44%) and hypertension (5 pts, 31%). Dose reduction was required for 11 of 16 pts (69%). Two pts were inevaluable after receiving <2 cycles due to AE (grade 4 hyponatremia; grade 3 fatigue) and 1 other pt has yet to complete 2 cycles. Conclusions: Sunitinib shows preliminary activity in EC. This trial will proceed to a second stage of accrual to further explore the efficacy and safety of sunitinib in advanced EC. [Table: see text]