One-year effectiveness study of intravitreous bevacizumab in neovascular age-related macular degeneration: a population-based retrospective cohort study.

Objective: To assess effectiveness of intravitreous bevacizumab in a cohort of patients with neovascular age-related macular degeneration (nAMD) in British Columbia, Canada.

Design: Retrospective cohort study.

Participants: Patients with new-onset AMD who completed 1 year of bevacizumab treatment.

Methods: A cohort of 4507 patients with nAMD (5174 eyes) aged 50 years and older treated on an as-needed basis with bevacizumab was followed from June 1, 2010, to May 31, 2014, and then evaluated after completing a follow-up treatment at 1 year. Descriptive statistics were used to characterize eyes treated with bevacizumab. Multivariable regression models were used to quantify visual acuity (VA) changes over time, adjusting for baseline prognostic variables.

Results: On average, patients received 8.6 injections (SD 2.4) per eye during the year of treatment. There was an average gain of 5.2 letters over the 1-year study period. Among eyes treated with bevacizumab, improvement in VA was greater for eyes with poorer baseline VA and for eyes receiving more injections. The odds ratio for VA at 1 year was 9.35 (95% CI 6.00-14.6) for eyes with VA 20/50-20/80 versus 20/20-20/40 and increased to 74.5 (95% CI 47.7-116.4) for eyes 20/400 or worse versus 20/20-20/40.

Conclusion: Intravitreous bevacizumab is effective in treating nAMD, especially for eyes with poor baseline VA. Gains in VA were greatest by month 3 and were generally maintained thereafter.