Future Treatments of Diabetic Retinopathy: Pharmacotherapeutic Products Under Development

Diabetic macular oedema (DMO) is the leading cause of vision loss in working aged individuals. Macular laser photocoagulation was the primary DMO treatment for several decades, but has recently been replaced by intravitreal injections of corticosteroids and drugs that inhibit the actions of vascular endothelial growth factor (VEGF). In Phase III trials, anti-VEGF drugs improve best corrected visual acuity by a mean of +12 letters, but up to 40% of patients have sub-optimal responses to therapy. The new anti-VEGF drugs abicipar and brolucizumab may possess extended durations of action in Phase III neovascular age-related macular degeneration trials, and DMO trials are being planned. Angiopoietin-2 inhibitors, both as co-formulations with anti-VEGF drugs and as bispecific antibodies, are in Phase II trials for DMO. Drugs that stimulate the Tie2 receptor are administered via subcutaneous injections. Intravenously administered antibodies that decrease diabetes-mediated inflammation, such as tocilizumab and teprotumumab, are entering early phase studies. Other drugs with topical (mecamylamine) and oral (minocycline) delivery routes are being developed. Several of these drugs may become available to patients within the next 5–10 years.