A systematic review and meta-analysis studied the efficacy of anti-vascular endothelial growth factor (anti-VEGF) monotherapy versus panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR) «Yates WB, Mammo Z, Simunovic MP. Intravitreal anti...»1. Randomized clinical trials included participants ≥18 years old with clinical or angiographic evidence of PDR and with Type 1 or Type 2 diabetes. The searches were performed on July 31, 2019. Interventions included were anti-VEGF monotherapy and PRP. Different anti-VEGF agents were employed, including bevacizumab, ranibizumab, and aflibercept. Follow-up varied between 6 and 24 months. Excluded studies were those with potentially biased treatment allocation and those offering combination therapies.
The primary outcome was mean change in best-corrected visual acuity. Secondary outcomes were the proportion of patients developing severe (<6/60) or moderate (6/24-6/60) vision loss, rates of vitrectomy or vitreous hemorrhage, worsening macula edema, and reduced visual field indices.
Primary outcome: Five studies of varying quality met the inclusion criteria (n = 632). The anti-VEGF intervention arm had a mean difference of -0.08 logMAR or 4 Early Treatment Diabetic Retinopathy Study (EDTRS) letters gained (p = 0.02) when compared with PRP at 12 months.
Secondary outcomes: The difference in rates of vitrectomy and vitreous hemorrhage favoured anti-VEGF over PRP (risk difference [RD] -0.10, p = < 0.001 and RD -0.10, p = 0.003 respectively). Patients who received anti-VEGF monotherapy were less likely to experience moderate vision loss when compared with patients undergoing PRP (RD -0.12, 95% -0.21 to -0.03, p = 0.01). For severe vision loss (logMAR 1.0 or VA 6/60 or less) there was no difference between anti-VEGF and PRP (RD -0.03, 95% CI -0.08 to 0.03, p = 0.93). Anti-VEGF monotherapy resulted in a lower incidence of centre-involving DME (CI-DME) at 12 months (RD -0.09; 95% CI -0.19 to -0.00, p = 0.05). Assessment of visual field function could not be pooled owing to differences in testing modalities. However, two studies comparing aflibercept and ranibizumab with PRP, favoured the anti-VEGF over PRP.
The aim of the study «Fallico M, Maugeri A, Lotery A, ym. Intravitreal a...»2 was to conduct a systematic review with network meta-analysis (NMA) of randomized clinical trials (RCTs) comparing panretinal photocoagulation (PRP) versus anti-vascular endothelial growth factor (VEGF) treatment alone or in combination with PRP, for proliferative diabetic retinopathy (PDR). The searches were performed on March 18,2020. Only English language RCTs with at least 6 months follow-up were included. Follow-up varied between 6 months and 5 years.
The primary outcome measures were the mean best corrected visual acuity (BCVA) change and the regression of neovascularization. Secondary outcomes were mean change of central macular thickness (CMT), the subgroup analyses of patients without diabetic macular oedema (DME) and the rate of vitreous haemorrhage and vitrectomy. Frequentist NMAs were performed.
Twelve RCTs with 1167 patients were included. VEGF treatments included were aflibercept, bevacizumab, pegaptanib and ranibizumab.
Primary outcome: For the 12-month mean BCVA change, NMA showed a better visual outcome in both the anti-VEGF group and combined group compared to PRP [anti-VEGF vs PRP, mean difference (MD) = 3.42; standard error (SE) = 1.5; combined vs PRP, MD = 3.92; SE = 1.65], with no difference between combined group and anti-VEGF (MD = -0.50; SE = 1.87).
Secondary outcomes: No difference in neovascularization regression was found between PRP and anti-VEGF alone or in combination with PRP, but there was significant inconsistency (p = 0.016). Subgroup analyses in patients without DME yielded no difference for the 12-month visual outcome between the three interventions, but with significant inconsistency (p = 0.005).