Twelve-month safety and visual acuity results from a feasibility study of intraocular, epiretinal radiation therapy for the treatment of subfoveal CNV secondary to AMD.

PURPOSE

The purpose of this study was to evaluate the short-term safety and feasibility of intraocular, epiretinal delivery of beta radiation for the treatment of subfoveal choroidal neovascularization secondary to age-related macular degeneration for 12 months. A 3-year follow-up period is planned to assess the long-term safety of the procedure.

METHODS

In this nonrandomized, multicenter feasibility study, 34 treatment-naïve patients with predominantly classic, minimally classic, or occult lesions due to subfoveal choroidal neovascularization secondary to age-related macular degeneration received a single treatment with either 15 Gray (Gy) (8 patients) or 24 Gy (26 patients) beta radiation (strontium-90) using a novel intraocular delivery device. Adverse events and safety endpoints were observed and recorded. Visual acuity was measured preoperatively and postoperatively using standard Early Treatment Diabetic Retinopathy Study vision charts.

RESULTS

Twelve months after treatment, no adverse events associated with exposure to radiation were observed. All patients in both 15 Gy (n = 4) and 24 Gy cohorts (n = 17) who met inclusion criteria and were treated according to protocol lost fewer than three lines of vision. Fifty percent (2/4) of the 15 Gy-treated patients and 76% (13/17) of the 24 Gy-treated patients improved or maintained their visual acuity at 12 months. In the 24 Gy group, 29% (5/17) gained three lines or more in visual acuity. The mean change in visual acuity observed at month 12 was +10.3 letters in the 24 Gy study cohort and -1.0 letters in the 15 Gy cohort.

CONCLUSION

The short-term safety and efficacy of intraocular, epiretinal delivery of beta radiation for the treatment of subfoveal choroidal neovascularization was promising in this small study group and should be studied in a larger cohort of patients.