Pazopanib (Paz) monotherapy in Asian women who have not progressed after first-line chemotherapy for advanced ovarian, Fallopian tube, or primary peritoneal carcinoma

Abstract

Background: Paz, an oral multikinase inhibitor of VEGF, PDGF and c-Kit has showed activity in advanced ovarian cancer. This study evaluated paz as maintenance therapy in Asian women with advanced ovarian cancer. Methods: Subjects with FIGO stage II, III, or IV ovarian, fallopian tube, or primary peritoneal cancer whose disease had not progressed after debulking surgery and followed by chemotherapy were randomized 1:1 to paz 800 mg once daily or placebo for up to 24 months. Primary endpoint was PFS by RECIST v1.0 based on visit date. If a progression occurred between the 2 scheduled visits (6 mos apart), progression was considered to have occurred at the next scheduled scan date. This minimized potential bias due to any imbalance of visit frequency between the arms. Results: 145 Asian subjects were randomized; 144 were treated. Mean age was 52.9 years. At diagnosis 17% were FIGO stage II, 73% stage III and 10% stage IV. After debulking surgery, 30% (n = 44) had no residual disease and 41% (n = 59) had. 47% (28/59) had residual disease ≤1cm. Prior to randomization, all subjects received median 8 cycles of chemotherapy; all subjects received platinum and taxane. At randomization 81% had ECOG status 0, 97% were disease free and all had normal CA-125. At clinical data cut-off median PFS was 18.1 months in both arms. Because of the small sample size a HR was not calculated but the KM curves indicated a trend in favor of paz from 6 to 18 mos; the curves crossed after 18 mos. The adverse event (AE) profile for paz was similar to previous reports except rates of hypertension and neutropenia were higher. The most frequent AEs (≥ 20%) on the paz arm were hypertension (76%), neutropenia (64%), leucopenia (53%), diarrhea (47%), hair color changes (40%), palm-plantar erythrodysaethesia syndrome (29%), ALT increase (28%), thrombocytopenia (24%), AST increase (22%) and TSH increase (21%). Most of these AEs were Grade 1-2. Conclusions: The results of this study alone cannot confirm the efficacy of paz maintenance treatment in Asian women with ovarian cancer, but should be interpreted in conjunction of AGO-OVAR16 study. Clinical trial information: NCT01227928.