Intraocular pharmacokinetics of bevacizumab after a single intravitreal injection in humans.

PURPOSE

To investigate intraocular concentrations and pharmacokinetics of bevacizumab after a single intravitreal injection in humans.

DESIGN

Prospective, noncomparative, interventional case series.

METHODS

We included 30 nonvitrectomized eyes of 30 patients (age range, 43 to 93 years) diagnosed with clinically significant cataract and concurrent macular edema secondary to neovascular age-related macular degeneration, diabetic retinopathy, or retinal venous occlusion in the same eye. All patients received an intravitreal injection of 1.5 mg bevacizumab. Between one and 53 days after injection, an aqueous humor sample was obtained during elective cataract surgery. Concentrations of unbound bevacizumab in these samples were quantified by enzyme-linked immunosorbent assay.

RESULTS

Concentration of bevacizumab in aqueous humor peaked on the first day after injection with a mean concentration (c(max)) of 33.3 microg/ml (range, 16.6 to 42.5 microg/ml) and subsequently declined in a monoexponential fashion. Nonlinear regression analysis determined an elimination half-time (t(1/2)) of 9.82 days (R(2) = 0.81). No significant differences between diagnosis subgroups were noted.

CONCLUSIONS

In human nonvitrectomized eyes, the aqueous half-life of 1.5 mg intravitreally injected bevacizumab is 9.82 days.