Bevacizumab before Diabetic Vitrectomy: A Clinical Trial Assessing 3 Dosing Amounts.

PURPOSE

To evaluate the optimal dosing of preoperative intravitreal bevacizumab (IVB) in patients undergoing pars plana vitrectomy (PPV) for manifestations of proliferative diabetic retinopathy (PDR).

DESIGN

Randomized clinical trial.

PARTICIPANTS

Two hundred six patients with severe manifestations of PDR underwent PPV at a single university-based hospital.

METHODS

Patients were randomized into 1 of 3 treatment groups: group A received 0.625 mg IVB (0.025 ml) 1 to 10 days before PPV, group B received 1.25 mg IVB (0.05 ml) 1 to 10 days before PPV, and group C received 2.5 mg IVB (0.1 ml) 1 to 10 days before PPV.

MAIN OUTCOME MEASURES

The primary outcome was best-corrected visual acuity (BCVA) at 6 months. Secondary outcome measures were rates of perioperative tractional retinal detachment (TRD) development, intraoperative and postoperative complications, and incidence of unplanned PPV at 6 months.

RESULTS

One hundred sixty-seven patients underwent PPV and completed 6 months of follow-up. There were no significant differences between treatment groups regarding baseline characteristics, final BCVA, intraoperative complications, postoperative complications, or unplanned PPV rates. There were no patients in group A (0.0%), 3 patients in group B (7.0%), and 5 patients in group C (8.5%) who demonstrated perioperative TRD after IVB administration, but before PPV (P = 0.0283). This difference was significant between groups A and B (P = 0.0494) and between groups A and C (P = 0.0080).

CONCLUSIONS

This randomized clinical trial demonstrated that patients receiving the 0.625-mg dose of IVB before PPV for the treatment of PDR-related manifestations showed similar visual acuity, but a lower incidence of perioperative TRD development compared with patients receiving the 1.25-mg and 2.5-mg doses. Clinicians should consider adopting the lowest effective dose, 0.625 mg, into clinical practice. The current study is limited by the lack of a control group receiving no IVB before PPV.