Evidence for Anti-vascular Endothelial Growth Factor Treatment of Diabetic Macular Oedema
from this trial suggest that subconjunctival rapamycin is safe in the treatment of patients with DME; however, conclusions cannot be drawn regarding its therapeutic efficacy in DME, since the findings could also be attributed to the natural history of DME or laser treatment. In order to demonstrate the possible therapeutic effect of rapamycin a large randomised clinical trial must be designed.
VEGF plays a key role in promoting angiogenesis and vascular leakage and today represents an attractive candidate as a therapeutic target in the treatment and management of diabetic retinopathy. The advent of intravitreal anti-VEGF drugs has opened a new era for the management of DME. While focal/grid laser remains a standard treatment for DME and is supported by evidence provided by large-scale studies,51
the use of anti-VEGF substances in clinical
practice has showed encouraging results. Most of the studies reported in this article were well-designed clinical trials with the objective of demonstrating both the therapeutic effect of anti-VEGF drugs and data regarding their safety. However, only larger trials can consolidate the use of anti-VEGF drugs in the clinical routine with the objective of creating guidelines for the management of DME. Another
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aspect that must be highlighted is the efficacy of anti-VEGF drugs over longer follow-up periods. Most controlled studies focus on one- or two-year results, but long-term results are unavailable. It would be of the utmost importance to demonstrate that anti-VEGF drugs are able to provide therapeutic effects over a long period of time, and to compare these effects with those of laser treatment, which is characterised by a slow, but sustained therapeutic effect that most likely is more efficient many years after its employment. The use of combination therapy including anti-VEGF and focal/grid laser treatment has provided encouraging results and must also be evaluated over a long timespan. In particular, the combination of laser application and intravitreal anti-VEGF can reduce the number of injections without a negative effect on visual function, in an attempt to lessen the burden of the therapy for both patients and doctors.
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