Abstract
Purpose: :
To evaluate the safety and efficacy of intravitreal Ranibizumab used in combination with photodynamic therapy (PDT) for the treatment of subfoveal choroidal neovascularisation secondary to AMD, compared to the use of intravitreal Ranibizumab monotherapy.
Methods: :
In this prospective one-year double-masked exploratory study patients were randomised to receive initial standard fluence PDT or sham PDT, with 3 monthly intravitreal injections of Ranibizumab in both groups. Thereafter patients were seen monthly and retreatment with Ranibizumab was given for both groups if there was a loss of >5 logMAR letters of BCVA associated with intra-retinal or sub-retinal fluid on the OCT, or a greater than 100 µm increase in central retinal thickness on OCT.
Results: :
18 patients were recruited. Both groups showed well-balanced baseline characeristics. There was a gain of ≥15 letters in 11.1% of the combination group and 22.2% in the monotherapy group at 11 months. No patient lost ≥15 letters of BCVA in either group. There was a trend for a lower mean BCVA gain in the combination group particularly in the first 4 months ( 3 letter mean gain in the combination group vs 6 letter mean gain with monotherapy 1 month after 3 loading doses of Ranibizumab), but no significant difference in the mean change in BCVA, change in log contrast sensitivity scores, change in reading speed or reduction in central retinal thickness between the two groups at all time points during the study. There was a significant reduction in the re-treatment rate by 6 months in the combination group, but by 12 months this was not significant with a mean number of additional injections of 1.3 for each group. The mean time to re-treatment was 4.6 months for the PDT group and 2.8 months for the sham group. All patients treated with PDT showed a circle of central choroidal hypofluoresence on fluorescein angiography at 1 month post-PDT and a circle of relative hypofluoresence persisted during follow-up angiography, even if there subsequently became evidence of recurrent CNV activity within this area.
Conclusions: :
There was a trend for less beneficial BCVA outcomes in the combination group, particularly during the first 4 months, although there was no significant difference in the mean change in BCVA between groups. There was no significant difference in re-treatments at 1 year between the groups. The fluorescein angiography findings raise questions about the use of standard fluence PDT in combination with Ranibizumab. Results from ongoing larger randomised controlled trials are awaited.
Clinical Trial: :
www.ISRCTN.org ISRCTN42639823 www.nrr.nhs.uk NO264194884
Keywords: age-related macular degeneration • vascular endothelial growth factor • photodynamic therapy