Conbercept for Treatment of Neovascular Age-related Macular Degeneration: Results of the Randomized Phase 3 PHOENIX Study

Purpose

Age-related macular degeneration (AMD) can cause irreversible vision loss leading to blindness. We aim to evaluate the efficacy and safety of intravitreal injections of 0.5 mg conbercept, a new anti–vascular endothelial growth factor (anti-VEGF) drug, for treatment of AMD on a schedule more manageable for patients.

Design

A prospective, double-masked, multicenter, sham-controlled, phase III randomized trial.

Methods

Patients: Patients with choroidal neovascularization (CNV) secondary to AMD were enrolled and randomized to the conbercept group or the sham control group. Intervention: The conbercept group received intravitreal injections of conbercept (0.5 mg) once monthly for the first 3 months, then once quarterly until month 12 (3 + Q3M). The sham group received first 3 monthly sham injections and then 3 monthly injections of conbercept (0.5 mg) followed by quarterly administrations until month 12. Main Outcome Measures: The primary endpoint was mean change from baseline in best-corrected visual acuity (BCVA) at month 3.

Results

A total of 114 patients (91.9%) from 9 sites in China completed the 12-month study. At the 3-month primary endpoint, the mean changes in BCVA from baseline were +9.20 letters in the conbercept group and +2.02 letters in the sham group, respectively (P < .001). At 12 months, the mean changes from baseline in BCVA letter score were +9.98 letters in the conbercept group and +8.81 letters in the sham group (P = .64). The most common ocular adverse events were associated with intravitreal injections, such as conjunctival hemorrhage, and increased intraocular pressure.

Conclusions

A conbercept dosing regimen of 3 initial monthly administrations followed by quarterly treatments is effective for treatment of AMD. In previous reports, other anti-VEGF agents were unable to maintain similar clinical benefits with the same regimen.