New approaches for the treatment of diabetic macular oedema: recommendations by an expert panel

Abstract

The current standard therapy for patients with diabetic macular oedema (DME)--focal/grid laser photocoagulation--usually does not improve impaired vision, and many patients lose vision despite laser therapy. Recent approval of ranibizumab by the European Medicines Agency to treat visual impairment due to DME fulfils the previously unmet medical need for a treatment that can improve visual acuity (VA) in these patients. We reviewed 1- and 2-year clinical trial findings for ranibizumab used as treatment for DME to formulate evidence-based treatment recommendations in the context of this new therapy. DME with or without visual impairment should be considered for treatment when it fulfils the Early Treatment Diabetic Retinopathy Study (ETDRS) criteria for clinically significant oedema. For DME with centre involvement and associated vision loss due to DME, monthly ranibizumab monotherapy with treatment interruption and re-initiation based on VA stability is recommended. Laser therapy based on ETDRS guidelines is recommended for other forms of clinically significant DME without centre involvement or when no vision loss has occurred, despite centre involvement. Because these recommendations are based on randomised controlled trials of 1-2 years duration, guidance may need updating as long-term ranibizumab data become available and as additional therapeutic agents are assessed in clinical trials.

Figure 1

BCVA outcomes over time in prospective, randomised clinical trials with ranibizumab in DME. (a) READ-2; (b) RESOLVE; (c) RESTORE; and (d) DRCR.net protocol I^b.^{, , , , a}Patients eligible to receive ranibizumab after month 6. ^bValues that were ±30 letters were assigned a value of 30. ^*P<0.0001 vs control; ^**P=0.0004 vs control; ^***P<0.001 vs sham+prompt laser; ^****P=0.03 vs sham+prompt laser. BCVA, best-corrected visual acuity; DME, diabetic macular oedema.

Figure 2

RESTORE subgroup analysis based on (a) baseline CRT and (b) baseline VA. CRT, central retinal thickness; DME, diabetic macular oedema; SE, standard error; VA, visual acuity.

Figure 3

Treatment algorithm for DME. ^aData at 1 year suggest that concomitant administration of ranibizumab and laser is not harmful; however, no added benefit of adding laser to ranibizumab therapy has been demonstrated. The addition of laser can be considered at the physician's discretion. When given on the same day, ranibizumab should be administered at least 30 min after laser photocoagulation. DD, disk diameter; DME, diabetic macular oedema; ETDRS, Early Treatment Diabetic Retinopathy Study.