Vascular Endothelial Growth Factor (VEGF) Trap-Eye provided a significant benefit to patients with diabetic macular edema in a phase II trial – and updated data now shows the initial improvements were sustained or increased a year later….
The 24-week results of the DA VINCI published study, showed that VEGF Trap-Eye intravitreal injections were significantly more effective than the standard treatment, laser photocoagulation, in both preserving and improving visual acuity.
VEGF Trap-Eye, developed by Regeneron Pharmaceuticals, Inc. (Tarrytown, New York) and Bayer Healthcare (Berlin, Germany), is a recombinant fusion protein that contains the VEGF binding domains of human VEGF receptors 1 and 2, fused to the Fc domain of human immunoglobulin G1.
Dr. Diana V. Do of The Wilmer Eye Institute in Baltimore, the study’s first author, stated that, while normal eyes contain some VEGF, the ischemic damage that occurs in diabetic eye disease up-regulates this protein and several other growth factors. High VEGF levels then cause additional damage to the blood vessels.
In the DA VINCI study, Dr. Do and her team compared five different treatment regimens: VEGF Trap-Eye 0.5 mg every four weeks; 2 mg every four weeks; 2 mg every eight weeks after three monthly doses; 2 mg as needed after three monthly doses; or macular laser photocoagulation.
At 52 weeks, average improvement in best-corrected visual acuity (BCVA) in the VEGF Trap Eye groups ranged from 9.7 to 13.1 letters, compared to -1.3 letters in the laser treatment group. Approximately 23.8% to 45.5% of eyes showed an improvement of 15 or more “Early Treatment of Diabetic Retinopathy Study” letters, compared to 11.4% of patients treated with laser therapy.
Mean reductions in central retinal thickness from baseline ranged from 165.4 to 227.4 micrometers in patients who received VEGF Trap-Eye, versus 58.4 micrometers for the laser treatment group.
Ocular adverse events associated with VEGF Trap-Eye were similar to those seen in other clinical trials with intravitreal VEGF inhibitors, the research team reports. There did not appear to be an increased risk of systematic arteriothrombotic events with the use of VEGF Trap-Eye.
Dr. Do stated that, “This is another piece of evidence to suggest that VEGF inhibitors are the best treatment for patients with diabetic macular edema because they are superior to laser for improving vision and reducing edema in the central retina.” “Over the past year and a half, we’ve had more level 1 evidence from randomized controlled trials showing that intravitreal VEGF inhibitors are superior in efficacy to lasers and even intravitreal steroids.”
Because VEGF Trap-Eye is a fusion protein with high affinity for VEGF, it may be more durable and have a longer effect than bevacizumab or ranibizumab, Dr. Do said.
The DA VINCI study demonstrated that VEGF Trap-Eye given every 8 weeks had similar efficacy compared to monthly administration of VEGF Trap-Eye. Dr. Do and her colleagues are now conducting a phase III trial and expect to have results ready for publication in a few years.
Ophthalmology Online, April, 24 2012.