Epimacular Brachytherapy Outcomes Do Not Match Anti-VEGF

Epimacular brachytherapy (EMB) results in inferior visual outcomes to anti-vascular endothelial growth factor (VEGF) injections for patients with chronic, active, neovascular age-related macular degeneration (nAMD), according to a study published in the British Journal of Ophthalmology. Additionally, patients who underwent the procedure did not require fewer anti-VEGF injection treatments, according to the research.

This study analyzed data from the MERLOT trial (​​ClinicalTrials.gov Identifier: NCT01006538). Patients with active nAMD were randomized to receive EMB plus as-needed monthly ranibizumab (n=244) or as-needed monthly ranibizumab monotherapy (n=119). Participants were assessed for best-corrected visual acuity (BCVA) and number of anti-VEGF injections through 36 months.

Patients had a mean age of 76.5±7.4 years, all were White, and more randomized to receive EMB were women (63.5% vs 52.1%).

Compared with baseline, BCVA decreased more greatly among the EMB recipients than the monotherapy cohort (mean difference [MD], -14.9; 95% CI, -18.5 to -11.2 ETDRS letters; P <.0001). The proportion of patients who lost fewer than 15 ETDRS letters (43.9% vs 79.8%; P <.0001) or experienced a gain of 15 ETDRS letters or more (0.0% vs 2.5%; P =.002) was lower in the EMB cohort. Similar trends were observed between months 24 and 36.

The EMB and monotherapy cohorts did not differ significantly for number of anti-VEGF injection between baseline and month 36 (MD, 0.7; 95% CI, -0.9 to 2.3; P =.41) or months 24 and 36 (MD, -0.3; 95% CI, -1.0 to 0.4; P =.43).

Given the poorer visual acuity in the EMB recipients, the investigators performed a post hoc analysis and found no significant differences at month 24 for area of fibrosis (P =.36), atrophic scar (P =.79), or geographic atrophy (P =.59) between groups.

The most frequent adverse event was clinically significant cataract (95.9% vs 32.2%) among phakic eyes in the EMB and monotherapy cohorts, respectively. More of the EMB group with phakic eyes received cataract surgery (84.5% vs 22.2%).

This study may have been limited by the lack of patient or clinician blinding.

These data indicated that EMB and ranibizumab dual therapy for nAMD were associated with poorer visual outcomes than ranibizumab therapy alone. In addition, EMB did not decrease the number of anti-VEGF injections needed. On the basis of these data, the investigators could not support the use of EMB for chronic, active, nAMD.

Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.

Reference

Jackson TL, Soare C, Petarca C, et al. Epimacular brachytherapy for previously treated neovascular age-related macular degeneration: month 36 results of the MERLOT randomized controlled trial. Br J Ophthalmol. 2022;bjophthalmol-2021-320620. doi:10.1136/bjophthalmol-2021-320620