The Diabetic Retinopathy Clinical Research Network (DRCR.net) supports the identification, design, and implementation of multicenter clinical research initiatives focused on diabetes-induced retinal disorders.1
Principal emphasis has been placed on clinical trials, with additional support of epidemiologic outcomes and other related studies.
DRCR.net currently includes more than 115 participating sites with over 400 physicians throughout the U.S. has initiated more than 25 studies, enrolled over 9,000 study participants, and has been responsible for some of the most important, care-changing clinical trials related to diabetic retinopathy (DR) and diabetic macular edema (DME) performed over the past 15 years.
DRCR.net was founded in September 2002 through a cooperative agreement with the U.S. National Institutes of Health to pool clinical research data from disparate retinal specialty practices with the goal of determining clinically meaningful and statistically significant treatment options for both DR and DME in the most expeditious fashion.1
DRCR.net receives funding for its research from the National Eye Institute (NEI) and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).
Previously by Dr. Chous: Role of insulin therapy in diabetes and diabetic retinopathy
The most important clinical trials conducted by DRCR.net include Protocols S, T, and I. These have significantly changed the way proliferative diabetic retinopathy (PDR) and DME—the leading cause of severe vision loss in diabetes patients—are managed.
Protocol S showed that intravitreal injection of the vascular endothelial growth factor (VEGF) inhibitor, ranibizumab (Lucentis, Genentech) is non-inferior to panretinal photocoagulation (PRP) for prevention of severe vision loss and regression of neovascularization in patients with PDR.
Predictably, subjects receiving anti-VEGF therapy maintained significantly better visual field and night-vision than those receiving PRP.2
Patients receiving injections were also significantly less likely to develop severe, center-involved DME (CI-DME) and more likely to experience resolution of any pre-existing DME.
Although anti-VEGF therapy for PDR is not a one-off treatment—and requires patient adherence with careful follow-up and repeat injections—Protocol S has established injections as a potential alternative to PRP, as well as a definitive complementary strategy that allows for fewer laser burns and better visual function.2
1. Jaeb Center for Health Research. General Information about the DRCR Retina Network. Available at: https://public.jaeb.org/drcrnet/view/General_Info. Accessed 7/9/19.
2. Writing Committee for the Diabetic Retinopathy Clinical Research Network, Gross JG, Glassman AR, Jampol LM, Inusah S, Aiello LP, Antoszyk AN, Baker CW, Berger BB, Bressler NM, Browning D, Elman MJ, Ferris FL 3rd, Friedman SM, Marcus DM, Melia M, Stockdale CR, Sun JK, Beck RW. Panretinal Photocoagulation vs Intravitreous Ranibizumab for Proliferative Diabetic Retinopathy: A Randomized Clinical Trial. JAMA. 2015 Nov 24;314(20):2137-2146.
3. Wells JA, Glassman AR, Ayala AR, Jampol LM, Bressler NM, Bressler SB, Brucker AJ, Ferris FL, Hampton GR, Jhaveri C, Melia M, Beck RW, Diabetic Retinopathy Clinical Research Network. Aflibercept, Bevacizumab, or Ranibizumab for Diabetic Macular Edema: Two-Year Results from a Comparative Effectiveness Randomized Clinical Trial. Ophthalmology. 2016 Jun;123(6):1351-9.
4. Bressler NM, Beaulieu WT, Glassman AR, Blinder KJ, Bressler SB, Jampol LM, Melia M, Wells JA 3rd, Diabetic Retinopathy Clinical Research Network. Persistent Macular Thickening Following Intravitreous Aflibercept, Bevacizumab, or Ranibizumab for Central-Involved Diabetic Macular Edema With Vision Impairment: A Secondary Analysis of a Randomized Clinical Trial. JAMA Ophthalmol. 2018 Mar 1;136(3):257-269.
5. Bressler SB, Glassman AR, Almukhtar T, Bressler NM, Ferris FL, Googe JM Jr, Gupta SK, Jampol LM, Melia M, Wells JA 3rd, Diabetic Retinopathy Clinical Research Network. Five-Year Outcomes of Ranibizumab With Prompt or Deferred Laser Versus Laser or Triamcinolone Plus Deferred Ranibizumab for Diabetic Macular Edema. Am J Ophthalmol. 2016 Apr;164:57-68.
6. Bressler NM, Beaulieu WT, Maguire MG, Glassman AR, Blinder KJ, Bressler SB, Gonzalez, Jampol LM, Melia M, Sun JK, Wells JA 3rd, Diabetic Retinopathy Clinical Research Network. Early Response to Anti-Vascular Endothelial Growth Factor and Two-Year Outcomes Among Eyes With Diabetic Macular Edema in Protocol T. Am J Ophthalmol. 2018 Nov;195:93-100.
7. Baker CW, Glassman AR, Beaulieu WT, Antoszyk AN, Browning DJ, Chalam KV, Grover S, Jampol LM, Jhaveri CD, Melia M, Stockdale CR, Martin DF, Sun JK, DRCR Retina Network. Effect of Initial Management With Aflibercept vs Laser Photocoagulation vs Observation on Vision Loss Among Patients With Diabetic Macular Edema Involving the Center of the Macula and Good Visual Acuity: A Randomized Clinical Trial. JAMA. 2019 Apr 29. doi: 10.1001/jama.2019.5790.