Purpose: The objective of this study was to determine the pharmacokinetics and safety for NX1838 following injection into the vitreous humor of rhesus monkeys.
Methods: Plasma and vitreous humor pharmacokinetics were determined following a single bilateral 0.25, 0.50, 1.0, 1.5, or 2.0 mg/eye dose. In addition, the pharmacokinetics and toxicological properties of NX1838 were determined following six biweekly bilateral injections of 0.25 or 0.50 mg/eye or following four biweekly bilateral injections of 0.10 mg per eye followed by two biweekly bilateral injections of 1.0 mg per eye.
Results: Plasma and vitreous humor NX1838 concentrations were linearly related to the dose administered. NX1838 was cleared intact from the vitreous humor into the plasma with a half-life of approximately 94 h, which was in agreement with the plasma terminal half-life. Vascular endothelial growth factor (VEGF)-binding assays demonstrated that the NX1838 remaining in the vitreous humor after 28 days was fully active. No toxicological effects or antibody responses were evident.
Conclusions: The no observable effect level was greater than six biweekly bilateral 0.50 mg/eye doses or two biweekly bilateral 1.0 mg/eye doses. These pharmacokinetic and safety data support monthly 1 or 2 mg/eye dose regimens in human clinical trials.