Year-2 Protocol T data paints different scenario from year-1
The Diabetic Retinopathy Clinical Research Network’s (DRCR.net) Protocol T—the first head-to-head-to-head comparison among aflibercept (Eylea, Renegeron Pharmaceuticals), ranibizumab (Lucentis, Genentech), and bevacizumab (Avastin, Genentech)—found in its first-year results that all three agents improved vision and reduced edema effectively.
However, the DRCR.net found differences in a pre-planned subanalysis of baseline vision, showing better outcomes with aflibercept than the other two anti-vascular endothelial growth factor (anti-VEGF) agents in patients with baseline vision worse than 20/50. That difference was depleted by Year 2.
"There were 660 eyes randomized, and we had great retention,” said John A. Wells, III, MD, “More than 95% of patients completed the primary outcome visit, and over 90% the final two-year visit.”
Year 2 results
There were no differences between the 3 groups in baseline characteristics that included vision, optical coherence tomography (OCT), central subfield thickness, and history of prior laser or anti-VEGF therapy, said Dr. Wells, who is in private practice in Columbia, SC.
As in other studies, “the number of injections required in the second year decreased by about 40% relative to the first year,” Dr. Wells said. “Overall, all three groups were given a median of 15 to 16 injections over the course of the 2 years of the study.”
In the first and in the second year, eyes in the aflibercept group were less likely to receive laser treatment than eyes in the other two groups. Compared to the first year, in the second year there was about a 50% reduction in the amount of laser applied in all three groups.
Overall, eyes in the aflibercept group were the least likely to receive laser, whereas eyes in the bevacizumab group were the most likely to receive laser at anytime over the 2 years.
The mean change in visual acuity at 2 years for the full cohort showed “the difference between aflibercept and ranibizumab had disappeared and was no longer significant, while aflibercept remains superior to bevacizumab,” Dr. Wells said.