Efficacy and safety of anti-VEGF monoclonal antibody 601 for macular oedema in retinal vein occlusion: two phase IIa randomised clinical trials.

BACKGROUND

While anti-vascular endothelial growth factor (VEGF) therapies are effective for macular oedema secondary to retinal vein occlusion (RVO), there remains a need for additional treatment options. This study evaluated the novel anti-VEGF agent 601 versus ranibizumab in patients with branch RVO (BRVO) or central RVO (CRVO).

METHODS

In two multicentre, randomised, double-masked, active-controlled phase IIa trials (NCT04667897, NCT04667910) conducted at 12 Chinese sites (2021-2022), 120 patients were assigned 1:1 to receive intravitreal 1.25 mg 601 or 0.5 mg ranibizumab every 4 weeks until week 20, followed by pro re nata dosing through week 48. Eligible patients had best-corrected visual acuity (BCVA) of 78-19 Early Treatment Diabetic Retinopathy Study letters and central subfield thickness ≥250 µm. The primary endpoint was change in BCVA at week 24.

RESULTS

At week 24, the adjusted mean BCVA change from baseline was +16.52 letters for 601 versus +17.79 letters for ranibizumab (adjusted mean difference: -1.27 letters (95% CI -5.439 to 2.891 letters)) in BRVO, and +13.81 letters versus +16.79 letters (adjusted mean difference: -2.97 letters (95% CI -10.488 to 4.540 letters)) in CRVO. Central retina thickness (CST) reduction was similar for both treatments. Both groups showed sustained improvements from week 24 to 52 with similar adverse event profiles.

CONCLUSIONS

These trials demonstrate that 601 is as effective and safe as ranibizumab for improving vision and reducing CST in RVO-related macular oedema. Phase III trials are warranted.