Fusion protein data for diabetic macular edema available soon

Baltimore-Following a promising phase I study of a fusion protein (VEGF Trap-Eye, Regeneron) in diabetic macular edema (DME), enrollment has been completed for a phase II study, and data will be available soon.

More than 50 of the 219 patients who have been treated have reached the 6-month primary endpoint, said one of the investigators, Diana V. Do, MD.

"VEGF is a critical stimulus for DME," Dr. Do said. "[The fusion protein] has many beneficial therapeutic qualities that make it a promising treatment for DME."

DA VINCI study

The current DME And VEGF Trap-Eye: INvestigation of Clinical Impact (DA VINCI) study is a randomized, multicenter, double-masked trial with sites in the United States, Canada, and Austria. Enrollment was completed in June 2009.

The study has five arms, four of which compare various doses of the fusion protein administered at different dosing intervals; subjects in the fifth study arm receive laser therapy every 16 weeks as needed.

The medical treatment groups are 0.5 mg of the fusion protein every 4 weeks, 2 mg every 4 weeks, 2 mg every 8 weeks, and 2 mg as needed.

At the primary endpoint of 24 weeks, patients in the fusion protein study arms qualify for laser re-treatment if DME still is present.

The primary outcome of DA VINCI is change in best-corrected visual acuity (BCVA) at week 24, while the secondary outcome is change in foveal thickness from baseline to week 24. The study is sponsored by Regeneron, in collaboration with Bayer Healthcare.

At baseline, the mean age of the patients in the study was 62.3 years; 41% were women. The vast majority (93.1%) had type 2 diabetes, and the mean hemoglobin A_1c (HbA_1c) was 8%. The mean central subfield thickness was 438.6 µm, and the mean BCVA was 59 letters.