Consider This Algorithm for Proliferative Diabetic Retinopathy
The Diabetic Retinopathy Clinical Research Network treatment algorithm for proliferative diabetic retinopathy (PDR) is a useful and effective tool in patients in whom anti-vascular endothelial growth factor (VEGF) and panretinal photocoagulation (PRP) are used as first-line therapy, according to a post hoc analysis of a randomized trial involving 394 eyes.
Participants had been randomized to receive either 0.5-mg intravitreous ranibizumab (n=191) or PRP (n=203). The ranibizumab group was given monthly injections for 6 months unless they had resolution after 4 injections. Thereafter injections could be deferred if neovascularization was consistent over 3 visits. PRP could be initiated for failure or futility criteria. Investigators looked at neovascularization through 2 years. Among the results:
- At 1 month, 2 in every 10 ranibizumab eyes experienced full neovascularization resolution.
- An additional 6 in 10 were considered improved.
- At 6 months, ~half had full resolution, 3% were improving, 37% were stable, and 8% had worsened.
- In eyes where neovascularization had resolved at 6 months, a median of 4 injections was required between 6 months and 2 years, vs 7 injections over that time in eyes that has not resolved.
- Injections were deferred in 93% of eyes; two-thirds resumed injections within 16 weeks.
- At 2 years, 43% had resolved, 5% were improved, 23% were stable, and 27% had worsened since the last visit.
- Only 3 eyes met criteria for failure or futility.
Sun J, Glassman A, Beaulieu W, et al. Rationale and application of the protocol S anti-vascular endothelial growth factor algorithm for proliferative diabetic retinopathy. Ophthalmology. 2019 Jan;126(1):87-95. doi: https://doi.org/10.1016/j.ophtha.2018.08.001.