A randomized phase II study of axitinib (AG-013736) and gemcitabine versus gemcitabine in advanced pancreatic cancer, preceded by a phase I component

Abstract

Listen

Translate article

4551 Background: The current standard of care for patients (pts) with advanced pancreatic cancer (APC) is gemcitabine (GEM)- based chemotherapy. Axitinib (AG) is a potent inhibitor of vascular endothelial growth factor receptors. A phase I study of AG in solid tumors identified 5 mg BID as the therapeutic starting dose. The main objectives of this trial are to determine whether the overall survival (OS) of the combination of AG and GEM is superior to that of GEM alone as first-line therapy in pts with APC, and to determine doses of AG and GEM that can be safely administered together. Methods: 8 pts were treated on the phase 1 (P1) portion of this trial. For the phase 2 (P2) portion of the trial, 103 pts with locally advanced or metastatic disease, no prior GEM or VEGF/VEGFR inhibitors, PS 0–2 were randomized (2:1) to GEM 1,000 mg/m2 over 30 minutes on days (D) 1, 8, 15 every 28 D with or without AG at a starting dose of 5 mg po BID between Jan 06 and Aug 06. CT scans were performed every 2 cycles. Results: Data from the evaluable P1 pts (n=5) indicated that PK of GEM and AG appeared to be unchanged in combination. The GEM mean plasma exposure (AUC) was 11,348 alone vs 12,840 ng.h/mL with AG; similarly mean steady-state AG AUC was 250 alone vs 270 ng.h/mL with GEM. 3 of 8 pts had a PR. The median number of days on study drug was 158 days (range: 57–330 days) with 2 pts ongoing. Data from the randomized P2 pts: male 48%; median age 62 (36- 81); PS 0/1 vs 2: 91% vs 9%; 41% with locally advanced disease; 59% with metastatic disease. The most commonly reported adverse events are anemia (48%), alk phos elevations (48%), leukopenia (45%), neutropenia (42%), LFT elevations (39%), and thrombocytopenia (27%). The most common non-hematologic adverse events are nausea (24%), vomiting (20%), fatigue (19%), diarrhea (18%), anorexia (18%), constipation (13%), dyspnea (12%), and pyrexia (12%). 55 events have been reported in the 103 P2 pts. The pooled median OS is 203 days with a 95% CI of (158, not estimable). The median follow-up time is currently 223 days. Conclusions: AG can be safely administered at a starting dose of 5 mg BID in combination with standard dose GEM in patients with APC. Final safety and OS results by treatment arm will be presented. [Table: see text]