Phase I Clinical Study of AZD2171, an Oral Vascular Endothelial Growth Factor Signaling Inhibitor, in Patients With Advanced Solid Tumors

Abstract

Purpose: AZD2171 is a highly potent oral selective inhibitor of vascular endothelial growth factor (VEGF) signaling. This phase I study was designed to evaluate the safety and tolerability of increasing doses of AZD2171, with additional assessments of pharmacokinetics, pharmacodynamics, and efficacy. Patients and Methods: In part A, 36 patients with solid tumors and liver metastases refractory to standard therapies received once-daily oral AZD2171 (0.5 to 60 mg). Doses were escalated in successive cohorts until the maximum-tolerated dose was identified. In part B, patients with (n = 36) or without (n = 11) liver metastases were randomly assigned to receive once-daily AZD2171 (20, 30, or 45 mg). In both parts, treatment continued until tumor progression or dose-limiting toxicity (DLT) was observed. Results: Eighty-three patients received AZD2171, which was generally well tolerated at doses of 45 mg/d or less; the most frequently reported dose-related adverse events were diarrhea, dysphonia, and hypertension. The most common DLT was hypertension (n = 7), which occurred at AZD2171 doses of 20 mg and higher. After a single dose, maximum plasma (peak) drug concentration after single-dose administration (C_max) was achieved 1 to 8 hours postdosing with an arithmetic mean half-life associated with terminal slope of a semilogarithmic concentration-time curve (t_1/2λz) of 22 hours. Pharmacodynamic assessments demonstrated time-, dose-, and exposure-related decreases in initial area under the curve, defined over 60 seconds post-contrast arrival in the tissue (iAUC₆₀) using dynamic contrast-enhanced magnetic resonance imaging, as well as dose- and time-dependent reductions in soluble VEGF receptor 2 levels. Preliminary evidence of efficacy included two confirmed partial responses and 22 patients with stable disease; effects on tumor size appeared to be dose related. Conclusion: Once-daily oral AZD2171 at doses of 45 mg or less was generally well tolerated and was associated with encouraging antitumor activity in patients with a broad range of advanced solid tumors.