In the treatment of vitreous hemorrhage from proliferative diabetic retinopathy, intraocular injection with anti–vascular endothelial growth factor (VEGF) shows similar efficacy to that of vitrectomy with photocoagulation; however, patients commonly require both treatments, new research shows.
“For patients who are experiencing visual loss from bleeding due to proliferative diabetic retinopathy, these strategies are both excellent treatments and can improve and then preserve visual acuity over six months to two years,” senior author Jennifer Sun, MD, of Harvard University, Cambridge, Massachusetts, said in a press statement.
“But there are some subtleties to this study that will help clinicians tailor their treatment plans for an individual patient,” added Sun, who is also chair of diabetes initiatives for the Diabetic Retinopathy Clinical Research (DRCR) Retina Network. The study by Andrew N. Antoszyk, MD, of Charlotte Eye, Ear, Nose and Throat Associates, Charlotte, North Carolina, and colleagues was published December 15 in JAMA.
The authors of an accompanying editorial agree that the results underscore the need to individualize treatment of proliferative diabetic retinopathy.
“While intravitreal injection of [an] anti-VEGF agent…may be a safe alternative to vitrectomy for the initial management of vitreous hemorrhage from proliferative diabetic retinopathy, vitrectomy with panretinal photocoagulation remains the standard care for this vision threatening complication for most patients,” write Tien Yin Wong, MD, PhD, of the Singapore Eye Institute, and colleagues.
However, this new study shows that “both clinical approaches have benefits and risks, and physicians treating patients with vitreous hemorrhage from proliferative diabetic retinopathy can and should personalize the initial therapeutic choice based on individual patient circumstances and influencing factors,” Sun and colleagues write.
For Anti-VEGF Therapy First, Patients Need Vitrectomy as Rescue Option
In proliferative diabetic retinopathy, abnormal new blood vessels grow (retinal neovascularization) and can bleed into the eyeball cavity, a complication known as vitreous hemorrhage. Left untreated, this can result in tractional retinal detachment, fibrosis, scarring, and blindness.
Vitrectomy has been the standard treatment for decades, but the procedure is costly, and fewer than 5% of ophthalmologists are trained as vitreoretinal surgeons. In addition, complications can occur ― the surgery often restores central vision, but the laser photocoagulation may reduce peripheral vision.
In contrast, intraocular anti-VEGF injections can be administered by general ophthalmologists and properly trained nurses in the clinic, but the therapy has caveats of its own, including the costs of increased ophthalmologist visits and repeated invasive administration of the drug, potentially over years.
To compare the two treatment approaches, the authors enrolled 205 participants with proliferative diabetic retinopathy at 39 DRCR Retina Network sites in the United States and Canada in the Protocol AB trial.
The participants were randomly assigned to undergo treatment in one eye each (total, 205 eyes), either with the anti-VEGF drug aflibercept (n = 100) or with prompt vitrectomy with laser photocoagulation (n = 105). The two groups were monitored for best corrected visual acuity over 2 years.
The mean age of the participants was 57 years. The mean visual acuity letter score was 34.5, the Snellen equivalent of 20/200.
For the primary outcome of the mean visual acuity letter score over 24 weeks, the vitrectomy and aflibercept groups did not differ significantly, at 63.0 and 59.3, respectively (P = .06).
At 2 years, there were still no significant differences, with a mean visual acuity letter score of 71.0 in the vitrectomy group and 73.7 in the aflibercept group (P = .36).
Over the 2 years, 33% of eyes treated with aflibercept were also treated with vitrectomy, and 32% of eyes in the vitrectomy group subsequently were treated with aflibercept.
More eyes among patients in the aflibercept group (22% vs 13% in the vitrectomy group) developed tractional retinal detachment, an expected finding, given the known risk from this sight-threatening complication secondary to anti-VEGF therapy (and the fact that prompt vitrectomy surgery also removes these areas of traction retinal detachment at the time the vitreous hemorrhage is removed).
However, the final visual acuity of eyes that developed tractional retinal detachment was similar to that of eyes without tractional retinal detachment. Importantly, the patients with tractional retinal detachments in the aflibercept group could receive prompt rescue vitrectomy and so did not have worse visual acuity outcomes.
“The implication is that patients should have access to early rescue vitrectomy surgery if anti-VEGF therapy with aflibercept is considered as the initial treatment option,” the editorialists stress.
Secondary Outcomes May Guide Therapy Choice
Secondary outcomes of the study may help guide initial therapeutic decision making, the authors note.
For instance, among patients in the vitrectomy group, vision was restored faster, and there was a reduced risk for recurrent vitreous hemorrhage (15% vs 49% in the aflibercept group; P < .001). The vitrectomy group also experienced less persistent retinal neovascularization (3% vs 29%; P < .001).
“For people with severe bleeds or who need to improve their vision quickly, surgery results in more rapid improvement,” Sun observed.
However, in the aflibercept group, there was a lower rate of diabetic macular edema involving the center of the macula (8% vs 31%; P < .001), and two thirds those patients were able to avoid vitrectomy.
So “for people who cannot receive surgery or prefer to avoid surgery if possible, anti-VEGF treatment still leads to equivalent visual outcomes over the long term,” she noted.
“Anti-VEGF injections may be used as an alternative for patients who may not have easy access to vitrectomy or are not candidates for surgery, have preexisting diabetic macular edema, and have a desire to avoid panretinal photocoagulation for other reasons such as maintaining their peripheral visual field,” the editorialists conclude.
The study was supported through a cooperative agreement from the National Eye Institute, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institutes of Health, and the US Department of Health and Human Services. Regeneron Pharmaceuticals Inc provided aflibercept for the study and funds to DRCR Retina Network to defray the study’s clinical site costs. Tan has received consulting fees from Alcon, Allergan, Bayer, and Novartis and grants from Santen. Other authors’ and editorialists’ relevant financial relationships are detailed in the published articles.