Regeneron Pharmaceuticals has reported initial results from the Protocol W trial of Eylea (aflibercept) injection, which showed a 68% reduced risk of developing vision-threatening complications in patients with moderate to severe non-proliferative diabetic retinopathy (NPDR), without centre-involved diabetic macular oedema (CI-DME).

Eylea is a VEGF inhibitor and formulated as an eye injection. It can potentially hinder the growth of new blood vessels and lower the chances of fluid passing through blood vessels in the eye by inhibiting VEGF-A and placental growth factor (PLGF).

The National Institutes of Health-sponsored, four-year, randomised, multi-centre, controlled trial analysed the efficacy of Eylea versus sham in preventing vision-threatening complications in high-risk patients.

In the trial, patients were randomised to receive either sham or 2mg Eylea every 16 weeks, after receiving four initial doses at zero, four, eight and 16 weeks.

The trial’s primary outcome at two years was time to development of CI-DME with vision loss or PDR.

Initial data showed that at two years, a 68% lower risk of developing vision-threatening complications (either PDR or CI-DME with vision loss) were observed in subjects receiving Eylea every 16 weeks.

Furthermore, patients who were given sham injections had almost five times more chances to experience disease progression needing EYLEA rescue therapy.

Regeneron president and chief scientific officer George Yancopoulos said: “Protocol W confirms the landmark results of the similarly-designed PANORAMA trial, underscoring the importance of early and regular diabetic retinopathy treatment and the ability of Eylea to substantially reduce vision-threatening complications and improve disease severity.

“Importantly, these results were obtained with an every-16-weeks Eylea dosing regimen, confirming the efficacy with Eylea seen in the PANORAMA trial.”

According to a recent follow-up analysis in a similar PANORAMA trial, delaying Eylea treatment resulted in three times as many patients suffering prolonged vision loss, versus those receiving preventive Eylea treatment, for two years.