Aqueous humor concentration of bevacizumab after subconjunctival injection in rabbit.

Purpose: To investigate whether bevacizumab may be delivered into the anterior chamber after subconjunctival administration and its pharmacokinetics in aqueous humor. Methods: The right eye of 33 rabbits received subconjunctival injection of 2.5 mg of subconjunctival bevacizumab. Three rabbits were sacrificed at each of the following time points: 0.5, 1, 2, 4, 8, 12, 24, 48, 72, 120, 168 h after the injection. Bevacizumab concentrations were measured in aqueous fluid of injected and uninjected eyes and serum using enzyme-linked immunosorbent assay. Results: Bevacizumab was first detected in the aqueous humor of the injected eye at 12 h after the subconjunctival injection. A peak concentration of 70.59 ± 26.01 ng/mL was achieved at 36 h. Bevacizumab was also detected in the serum and aqueous humor of the uninjected contralateral eye. The concentration in the aqueous humor of the injected eye was lower than in the serum and higher than in the aqueous humor of the uninjected contralateral eye at all time poi...