Purpose: To evaluate whether a less frequent bevacizumab dosing schedule after repeated doses in short intervals would be effective in patients with subfoveal choroidal neovascularization secondary to age-related macular degeneration.
Methods: Twenty-seven treatment-naive eyes of patients with subfoveal choroidal neovascularization secondary to age-related macular degeneration participated in this prospective, noncomparative, and interventional study at the Ulucanlar Eye Training and Research Hospital retina clinic. All lesion types were included. Intravitreal injections (1.25 mg/0.05 mL) of bevacizumab were given with a 6-week interval (Day 0, 6 weeks, and 12 weeks) for 3 months and then given at every 12-week interval up to 48 weeks. Main outcome measures of treatment were mean change in visual acuity and foveal center point retinal thickness from baseline documented by optical coherence tomography at 6, 12, 24, 36, and 48 weeks. The effects of patient age, baseline visual acuity, lesion composition, and lesion size on final visual acuity and loss of <15 letters of logarithm of the minimum angle of resolution (logMAR) at 48 weeks were also assessed.
Results: Of the 27 eyes, 24 eyes of 24 patients (14 men and 10 women) completed the 48-week follow-up and study protocol. Compared with baseline (0.95 ± 0.27 on Early Treatment Diabetic Retinopathy Study charts), mean best-corrected visual acuity improved to 0.77 ± 0.21 logMAR (P < 0.001) at Week 6, to 0.74 ± 0.2 logMAR (P < 0.001) at Week 12, to 0.79 ± 0.257 logMAR (P = 0.03) at Week 24, to 0.85 ± 0.26 logMAR (P = 0.54) at Week 36, and to 0.87 ± 0.27 logMAR (P = 1) at Week 48. The baseline mean center point retinal thickness that was 343 ± 64 μm decreased to 236 ± 40 μm (P < 0.001) at Week 6, to 222 ± 39 μm (P < 0.001) at Week 12, to 237 ± 37 (P < 0.001) at Week 24, to 253 ± 44 μm (P < 0.001) at Week 36, and to 268 ± 58 μm (P = 0.002) at Week 48. The maximal visual benefit obtained during the frequent dosing schedule significantly decreased by doses every 12 weeks at 48 weeks (P < 0.001). This decline in the best-corrected visual acuity gain was associated with an increase in the mean center point retinal thickness on optical coherence tomography. Patients aged <70 years and those having a baseline vision of 20/200 or worse were more likely to gain vision at 48 weeks (P = 0.001 and P = 0.02, respectively). In addition, a lesion ≤ 4 disk areas at baseline was less likely to lose <15 letters from baseline at 48 weeks (P = 0.03). No serious ocular and nonocular adverse events were noted.
Conclusion: Although intravitreal bevacizumab administration on a schedule of a 6-week injection interval for 3 months followed by every 12-week interval for neovascular age-related macular degeneration provided an improvement or stabilization in best-corrected visual acuity with anatomical improvement. This dosing strategy is unable to maintain the visual acuity and optical coherence tomography benefits seen with more frequent dosing.