Factors Linked to Injection Interval Extension in Eyes with Wet Age-Related Macular Degeneration Switched to Brolucizumab

Abstract

To evaluate factors associated with anti-vascular endothelial growth factor (VEGF) injection interval extension in patients with neovascular age-related macular degeneration (nAMD) switched to brolucizumab treatment. Retrospective, observational cohort study. Adults in the United States-based IRIS® Registry (Intelligent Research in Sight) with nAMD who switched from another anti-VEGF agent to brolucizumab-only treatment for ≥ 12 months from October 8, 2019, through November 26,2021. Univariable and multivariable analyses examined associations of demographic and clinical characteristics with the likelihood of interval extension after switching to brolucizumab therapy. Eyes were classified as either extenders or nonextenders at 12 months. Extenders were eyes that achieved (1) an extension of ≥ 2 weeks in the brolucizumab injection interval at 12 months versus the interval before switching (time between the last known prior anti-VEGF injection and first [index] brolucizumab injection) and (2) stable (< 10 letters gained or lost) or improved (≥ 10 letters gained) visual acuity (VA) at 12 months versus VA at index injection. Of 2015 eyes among 1890 patients who switched to brolucizumab treatment, 1186 (58.9%) were extenders. In univariable analyses, demographic and clinical characteristics were comparable between extenders and nonextenders, except that extenders had shorter intervals before switching versus nonextenders (mean, 5.9 ± 2.1 weeks vs. 10.1 ± 7.6 weeks, respectively). In multivariable logistic regression modeling, a shorter interval before switching was associated significantly and positively with interval extension with brolucizumab therapy (adjusted odds ratio, 5.6 for interval before switching of < 8 weeks versus ≥ 8 weeks; 95% confidence interval, 4.5-6.9; P < 0.001), and eyes with an index VA of 40 to 65 letters were significantly less likely to be extenders than eyes in the higher (better) index VA categories. Length of the treatment interval before switching was the characteristic associated most strongly with successful interval extension with brolucizumab. Treatment-experienced patients who required more frequent injections (i.e., shorter intervals before switching) showed the greatest extensions when switching to brolucizumab. With careful consideration of benefits and risks, brolucizumab may be a valuable option for patients with higher treatment burdens because of the need for frequent injections. Proprietary or commercial disclosure may be found after the references.