Abstract
Purpose :
Intravitreal injections of anti- vascular endothelial growth factor (anti-VEGF) agents
are considered the gold standard for treatment for diabetic macular edema (DME). While
monthly and as needed (PRN) injections schemes have been shown to be effective, they
constitute a burden for patients and providers in real world clinical settings. Alternatively, treat
and extend (T&E) dosing can be used titrate the anti-VEGF dosing based on an individual’s
clinical response while minimizing treatment burden. This study aims to pool available data on
change in visual acuity (VA), number of injections, and change in central subfield thickness
(CST) as reported by T&E regimens for DME compared to monthly and PRN regimens.
Methods :
PubMed, Science Direct, and EMBASE databases were queried for studies that met
the following criteria: retrospective or prospective design, T&E regimen reported in comparison
to a monthly or PRN regimen for the treatment of DME, and a 12 month follow up period. After
data were extracted, analysis was performed using a random effect model. Publication bias was
examined using a funnel plot and Egger’s linear regression test. An I^2 test was utilized to
determine heterogeneity.
Results :
Six total randomized clinical trials were identified. Three studies compared monthly
regimens to T&E. The remainder compared PRN regimens to T&E. Comparing monthly and
T&E regimens, no significant difference was found between average VA improvement (p=0.30),
CST improvement (p=0.28), or number of injections (p=0.20). Comparing PRN and T&E
regimens, no significant difference was found between average VA improvement (p=0.64), CST
improvement (p=0.11), or number of injections (p=0.89).
Conclusions :
In terms of VA and CST, T&E regiments were non-inferior to monthly or PRN
regiments. No significant difference in number of injections was detected. These conclusions are
limited by study design and outcome: only six studies, which included conservative T&E
regimens were included. Furthermore, the criteria did not filter for treatment naïve patients.
Future studies need to characterize the long-term reduction of treatment burden in T&E
protocols.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.