Background: Fundus albipunctatus is a retinal dystrophy caused by a mutation in the gene encoding 11-cis-retinol dehydrogenase which delays the recovery of rod photoreceptor cells from light stimulation leading to night blindness. A recent study of a mouse model of fundus albipunctatus treated with 9-cis-retinal showed improvement in visual function and structure.
Methods: Seven patients with fundus albipunctatus were given a daily food supplement of four capsules containing high dose 9-cis β-carotene for 90 days. The subjects were tested before and after treatment by visual field and electroretinogram in both eyes. This nonrandomized prospective phase I study was registered at www.clinicaltrials.gov (NCT00478530).
Results: All patients showed significant improvements in peripheral visual field (mean deviation improved from –4.77 ± 2.0 to –3.28 ± 2.28, P = 0.009, t-test).and highly significant improvement in rod recovery rates measured electroretinographically (Maximal scotopic b-wave amplitude responses, improved from 197 ± 49 µV to 292 ± 48 µV, P < 0.001, t-test). No complications or side effects were observed.
Conclusion: Oral treatment with 9-cis β-carotene led to reversal of a human retinal dystrophy. This potential therapy is readily available and should be evaluated in retinal dystrophies of similar mechanisms such as various types of retinitis pigmentosa.