A novel treatment approach for diabetic macular edema (DME) may offer comparable short-term outcomes to standard anti-VEGF therapy while substantially reducing the number of intravitreal injections required, according to a new study published in Eye Discovery.
Researchers from multiple centers in China evaluated a sequential “1 + 1 + PRN” regimen in treatment-naïve DME patients. The strategy involves one or two initial anti-VEGF injections, followed four weeks later by a dexamethasone (DEX) intravitreal implant, with subsequent anti-VEGF treatment administered on a pro re nata (PRN) basis. Outcomes were compared with the conventional “3 + PRN” protocol of three monthly anti-VEGF injections followed by PRN retreatment.
The retrospective study included 28 eyes from 23 patients and followed them for 25 weeks. Twelve eyes received the sequential regimen, while 16 eyes were treated with the standard anti-VEGF protocol. Investigators assessed best-corrected visual acuity (BCVA), central macular thickness (CMT), optical coherence tomography angiography (OCTA) biomarkers, and safety outcomes throughout the study period.
Both treatment approaches produced significant improvements in visual acuity and retinal anatomy. By week 25, BCVA had improved significantly from baseline in both groups, while CMT, hyperreflective foci, and cyst area within the deep capillary plexus also showed meaningful reductions. Importantly, no statistically significant differences were detected between the two treatment arms for these key efficacy endpoints.
Although the study was not powered to demonstrate superiority, the sequential regimen showed several encouraging trends. Patients receiving the DEX-containing approach achieved earlier visual gains and exhibited more stable visual outcomes over time. Anatomically, retinal thickness declined in a steady fashion, whereas the conventional anti-VEGF group demonstrated greater fluctuations during follow-up. Notably, DME recurrence was observed in three eyes treated with the standard 3 + PRN regimen but in none of the eyes managed with the sequential strategy.
The most striking difference between groups was treatment burden. Patients in the “1 + 1 + PRN” cohort required an average of just 2.6 injections during follow-up, compared with 4.9 injections in the conventional treatment arm – a reduction of almost 48 percent. The study authors suggest that fewer injections could lessen both the financial costs and psychological burden associated with frequent clinic visits and repeated intravitreal procedures.
The rationale behind the approach reflects the multifactorial nature of DME. While anti-VEGF agents remain the first-line standard of care, inflammation also plays a key role in disease pathogenesis. Dexamethasone implants provide sustained anti-inflammatory activity while also suppressing VEGF expression, potentially extending treatment durability beyond that achieved with anti-VEGF therapy alone. The authors argue that introducing corticosteroid therapy early may help to address both vascular and inflammatory drivers of edema, reducing the need for further repeated injections and lessening the economic burden for patients.
The safety findings of the new strategy were reassuring. Elevated intraocular pressure occurred more frequently in the sequential-treatment group, but the difference was not statistically significant, and all cases were successfully managed with topical medication. No serious ocular adverse events (e.g. retinal detachment, endophthalmitis or cataract progression) were reported in the study.
The investigators do acknowledge several limitations, including the study’s small sample size, retrospective design, short follow-up period, and non-randomized treatment allocation. Larger prospective trials will be needed to confirm whether the apparent advantages in durability and reduced treatment burden translate into long-term clinical benefit.
Nevertheless, the findings suggest that for some patients with newly diagnosed DME, an early transition from anti-VEGF therapy to sustained-release dexamethasone could maintain visual and anatomical outcomes while reducing the number of injections required in the long term.
