Relationship between OCT biomarkers and number of intravitreal ranibizumab injections in eyes with nAMD in the HARBOR study

To correlate baseline spectral domain optical coherence tomography (SD-OCT) characteristics with the number of as-needed intravitreal injections of ranibizumab over a 24-month follow-up period in eyes with neovascular age-related macular degeneration (nAMD). 236 eyes of 236 subjects with nAMD treated with ranibizumab 0.5 mg PRN in the HARBOR study were enrolled. Baseline SD-OCT images were evaluated by certified reading center graders for specific morphologic features of the macular neovascularization (MNV) lesion and surrounding retina. Baseline OCT features and patient demographics were correlated with the number of injections over the next two years. The mean number of injections in the 0.5mg PRN group was 8.07 (median 8, 3-12) after 12 months and 14.25 (median 14, 3-24) after 24 months of treatment. After multivariate linear regression analysis, the only baseline parameter that was independently associated with a higher injection frequency at both 12 and 24 months was a greater baseline SRF thickness. A greater SRF thickness at baseline was associated with a higher frequency of PRN injections over 12 and 24 months in eyes treated with ranibizumab for neovascular AMD. These findings may be of value in counseling patients who are about to initiate therapy for MNV.