No Difference in Vision Using Anti-VEGF or Surgical Approach for Proliferative Diabetic Retinopathy

December 16, 2020
Patrick Campbell

A randomized trial sponsored by the National Eye Institute is comparing the effects of a surgical vs anti-VEGF therapy in patients with proliferative diabetic retinopathy.

A new study from the National Eye Institute is providing evidence that suggests there is little difference in treatment effect between patients with diabetic retinopathy undergoing surgery versus those receiving anti-VEGF injections.

The study, which compared the effects of aflibercept to vitrectomy surgery and laser photocoagulation, found there was no significant difference in visual acuity letter score up to 2 years after treatment.

"There have been major advances in surgical technology and technique since the initial studies that evaluated surgical treatment of PDR,” said Jennifer Sun, MD, Harvard University, Cambridge, Massachusetts, chair of the Diabetes Initiatives with the DRCR Retina Network, in a statement. “This latest DRCR Retina Network study lets us understand how outcomes in the modern era of retinal surgery compare to treatment with intraocular anti-VEGF injections for vitreous hemorrhage from PDR."

With no clear determination on the best management approach for treatment of vitreous hemorrhage from proliferative diabetic retinopathy, Sun and a team of investigators from the DRCR Retina Network sought to design a study to compare approaches with intravitreous aflibercept compared to vitrectomy with panretinal photocoagulation. Using 39 DRCR sites across the US and Canada, investigators enrolled 205 adults in their trial between November 2016 to December 2017.

Patients in the study were randomly assigned to either study arm, with 100 being randomized to aflibercept and 105 to the surgical intervention. Patients randomized to aflibercept received 4 monthly injections and those randomized to surgery underwent vitrectomy with panretinal photocoagulation within 2 weeks of randomization. Investigators also pointed out both groups could receive either treatment during the follow-up period based on protocol criteria. The final follow-up visit of the trial was completed in January 2020.

The primary outcome of the trial was mean visual acuity letter score over 24 weeks. Secondary outcomes for the trial included visual acuity at 4 weeks and 2 years. Investigators noted the study was powered to detect a difference of 8 letters.

The mean age of patients randomized in the trial was 57 (SD, 11) years, 56% were men, and the mean visual acuity letter score was 34.5 letters. Of the 205 patients who underwent randomization, 95% completed the 24-week visit and 90% completed the 2-year visit.

Upon analysis, investigators found the mean visual acuity letter score over 24 weeks was 59.3 (Snellen equivalent, 20/63; 95% CI, 54.9-63.7) in the aflibercept group and 63.0 (Snellen equivalent, 20/63; 95% CI, 58.6-67.3) in the vitrectomy group, which resulted in an adjusted difference of -5.0 (95% CI, -10.2 to 0.3; P=.06). In secondary analyses, which assessed 23 outcomes, results indicated no significant difference in 15 outcomes.

At 4 weeks, the mean visual acuity letter score was 52.6 (Snellen equivalent, 20/100) in the aflibercept group and 62.3 (Snellen equivalent, 20/63) for those in the surgery group, which resulted in an adjusted difference of -11.2 (95% CI, -18.5 to -3.9; P=.03). At 2 years, the mean visual acuity letter score was 73.7 (Snellen equivalent, 20/40) in the aflibercept group and 71.0 (Snellen equivalent, 20/40) for those in the surgery group, which resulted in an adjusted difference of 2.7 (95% CI, -3.1 to 8.4; P=.36). Additionally, at 2 years, investigators found 33% of eyes assigned to aflibercept received vitrectomy and 32% of eyes assigned to vitrectomy received subsequent aflibercept.

“For patients who are experiencing visual loss from bleeding due to PDR, these strategies are both excellent treatments and can improve and then preserve visual acuity over six months to two years," said Sun.

This study, “Effect of Intravitreous Aflibercept vs Vitrectomy With Panretinal Photocoagulation on Visual Acuity in Patients With Vitreous Hemorrhage From Proliferative Diabetic Retinopathy,” was published in the Journal of the American Medical Association.