The incidence of
diabetic retinopathy is still increasing in developed countries. Tight
glycemic control and
laser therapy reduce vision loss and
blindness, but do not reverse existing ocular damage and only slow the progression of the disease. New pharmacologic agents that are currently under development and are specifically directed against clearly defined biochemical targets (i.e.
aldose reductase inhibitors and
protein kinase C-beta inhibitors) have failed to demonstrate significant efficacy in the treatment of
diabetic retinopathy in clinical trials. In contrast,
calcium dobesilate (2,5-dihydroxybenzenesulfonate), which was discovered more than 40 years ago and is registered for the treatment of
diabetic retinopathy in more than 20 countries remains, to our knowledge, the only angioprotective agent that reduces the progression of this disease. An overall review of published studies involving
calcium dobesilate (
CLS 2210) depicts a rather 'non-specific' compound acting moderately, but significantly, on the various and complex disorders that contribute to
diabetic retinopathy. Recent studies have shown that
calcium dobesilate is a potent
antioxidant, particularly against the highly damaging
hydroxyl radical. In addition, it improves diabetic endothelial dysfunction, reduces apoptosis, and slows vascular cell proliferation.