Trial of Dexamethasone Plus Ranibizumab for Persistent DME
JAMA Ophthalmology, January 2018
Although anti–vascular endothelial growth factor (anti-VEGF) therapy is often effective for diabetic macular edema (DME), some patients experience persistent edema and decreased visual acuity despite monthly injection. In a phase 2 randomized clinical trial, Maturi et al. added dexamethasone (known to reduce retinal thickening) to ongoing ranibizumab treatment to see if visual outcomes could be improved for patients with persistent DME. After 24 weeks of treatment, visual acuity was no better for patients on combination therapy than for those on ranibizumab alone.
The trial was conducted at 40 U.S. sites between February 2014 and December 2016. Adults who had DME despite ≥ 3 anti-VEGF injections in the previous 20 weeks received 3 additional ranibizumab injections during a 12-week run-in phase. Their visual acuity ranged from 20/32 to 20/320. Eligible patients with persistent DME continued ranibizumab injections and were assigned randomly to receive 700 μg of dexamethasone (combination group) or sham treatment (ranibizumab group). Treatments were administered as often as every 4 weeks, with the schedule based on a structured protocol. The main outcome measure was change in visual acuity letter score from randomization to week 24.
Among the 116 patients (median age, 65 years; 129 eyes), 65 eyes underwent combination treatment and 64 had ranibizumab alone. At 24 weeks, mean (standard deviation [SD]) visual acuity had improved by 2.7 (9.8) letters in the combination group and 3.0 (7.1) letters in the ranibizumab group (adjusted group difference, 0.5 letter; p = .73). Mean (SD) change in central subfield thickness was 110 (86) and 62 (97) μm, respectively (adjusted group difference, 52; p < .001). Increased intraocular pressure or initiation of antihypertensive eyedrops was reported for 29% of eyes in the combination group and for 0 eyes in the ranibizumab group (p < .001).
Despite the significantly greater reduction in retinal thickness in the combination group, adding dexamethasone to ranibizumab treatment did not lead to greater improvement in vision in patients with persistent DME compared to ranibizumab with a sham dexamethasone injection.
The original article can be found here.