Anti-VEGF treatment for retinal angiomatous proliferation

Background. Retinal angiomatous proliferation (RAP) is a subform of neovascular age-related macular degeneration (AMD), which is characterized by a particularly poor prognosis. The aim of this study is to describe the loading phase and maintenance phase for RAP during intravitreal anti-VEGF treatment. Material and methods. A total of 82 eyes in 82 patients with RAP stages 1-3 were treated during upload therapy with repeated intravitreal injections of 1.25 mg bevacizumab at intervals of 4 weeks until the retinal edema resolved. Baseline examination included measurement of the best corrected distance visual acuity (ETDRS chart), central retinal thickness using optical coherence tomography (OCT), and fluorescein angiography (FLA). During maintenance therapy, the patients' distance visual acuity was monitored at 4- to 12-week intervals and OCT or FLA performed if needed. The average follow-up was 7.4 months (SD 4.2). Treatment with intravitreal anti-VEGF therapy was repeated if there was evidence of sub- or intraretinal fluid with a decrease in visual acuity of 5 points or more, increase of the central retinal thickness of 100 mu m or more on OCT, or subjective deterioration with verifiable sub- or intraretinal fluid. Results. During upload therapy an improvement in visual acuity of an average of +5.1 letters (mean, n=82 eyes) was observed. During maintenance therapy it was initially possible to sustain this treatment effect. However, 5 months after loading therapy was concluded, a deterioration of -5.5 letters (mean, n=31) was evident in comparison with the end of loading therapy. During the further course deterioration continued (12-month follow-up: -8.6 letters, n=7). Recurrence occurred in 60% of the cases, on average 8 weeks after termination of loading therapy. During an observation period of 6 months (n=66) a total of 3.6 injections were necessary. Conclusions. Therapy with intravitreal anti-VEGF medications represents a treatment option for RAP, but in the long term the disease continues to progress accompanied by functional deterioration. We thus recommend that patients with RAP be monitored at 4-week intervals to permit early treatment of recurrence.