abstract: Phase 1 Dose-Escalation Study of Aflibercept Plus Docetaxel

Phase 1 Dose-Escalation Study of Aflibercept Plus Docetaxel:

Purpose: This phase I study cohort investigated aflibercept in combination with docetaxel in patients with advanced solid tumors.

Materials and Methods: Eligible patients had metastatic or nonresectable cancer for which docetaxel was considered appropriate. Patients received intravenous aflibercept (either 2, 4, 5, 6, 7, or 9 mg/kg) with docetaxel (75 mg/m²) on day 1 every 3 weeks until disease progression or unacceptable toxicity. Primary objectives were to evaluate dose-limiting toxicities (DLT) during cycle 1 and to determine the aflibercept recommended phase II trial dose (RP2D) for combination with docetaxel. Pharmacokinetics, tolerability, and antitumor activity were also investigated.

Results: Fifty-four patients (mean age, 56 y) were enrolled. Most had prior chemotherapy (96%) and most (24.1%) had breast cancer. In the dose-escalation phase (n = 34), there were three DLTs: grade 4 neutropenic infection (2 mg/kg), grade 3 dysphonia (7 mg/kg), and grade 2 hypertension (9 mg/kg). An excess of free-over-bound aflibercept was observed at doses of 5 mg/kg or more. The pharmacokinetics of aflibercept and docetaxel were not modified by coadministration. Aflibercept (6 mg/kg) was defined as the RP2D based on DLT and pharmacokinetic data.
Overall, the most frequent grade 3/4 adverse events (AE) were neutropenia (85.2%), leukopenia (74.1%), hypertension (18.5%), and stomatitis (16.7%). AEs associated with vascular endothelial growth factor blockade included epistaxis (all grades, 83.3%), proteinuria (68.5%), dysphonia (68.5%), and hypertension (53.7%). Seven patients had partial responses, and 32 patients had stable disease (>3 months in 18 patients).

Conclusion: On the basis of findings from this study, aflibercept (6 mg/kg) was the dose recommended for further clinical development. Clin Cancer Res; 18(6); 1743–50. ©2012 AACR.