A phase I and pharmacokinetic study of continuous infusion EMD 121974 (EMD), an antiangiogenic αvβ3 and αvβ5 integrin antagonist, in patients with advanced solid malignancy

Abstract

3052 Background: Integrins αvβ3 and αvβ5 are cell-surface receptors that play a significant role in angiogenesis by mediating the ligation signal that allows endothelial cells to attach to the extracellular matrix. These integrins share the binding epitope Arg-Gly-Asp (RGD). EMD is an RGD-containing cyclic pentapeptide. In clinical studies to date, EMD has been administered in an intermittent fashion. However, EMD has a short half-life of 3–5 hours with no evidence of drug accumulation. These data prompted the initiation of this phase I study of continuous infusion EMD. Methods: EMD was administered as a continuous infusion without break in 4-week cycles. Plasma samples for pharmacokinetic studies were obtained weekly in cycle 1 immediately prior to and 2 hours after infusion bag change. Results: To date 21 patients (15 male/6 female, median age 56, median Karnofsky performance status 90%) have been treated at the following dose levels: 1, 2, 4, 8, 12, 18, and 27 mg/h. Hematologic toxicities have been limited to grade 2 anemia and grade 3 lymphopenia. Non-hematologic toxicities have been limited to grade ≤ 2 and include alopecia, anorexia, diarrhea, fatigue, hypokalemia, hyponatremia, hypophosphatemia, insomnia, mucositis, nail changes, nausea, and transaminase elevation. One patient treated at 27 m/h experienced an unobserved death of unknown cause after two weeks of therapy. Pharmacokinetic analysis has been completed for patients treated at the 12 mg/h dose level and below. Mean values for half-life, clearance, and volume of distribution were comparable across dose levels, and steady-state concentration increased proportionally to dose. Conclusions: EMD can be safely administered as a continuous infusion at doses of up to at least 18 mg/h. No single toxicity has been consistently observed. A patient death in cycle 1 has resulted in the expansion of the 27 mg/h dose level. The pharmacokinetics of continuous infusion EMD were predictable and in general agreement with the published data of twice weekly infusion. Study enrollment is ongoing. [Table: see text]