Effect of Nilvadipine on Central Visual Field in Retinitis Pigmentosa: A 30-Month Clinical Trial

Abstract

Purpose: To assess the effects of nilvadipine on the progression of central visual field defect in retinitis pigmentosa (RP). Design: Prospective, randomized, nonmasked, single-center trial. Methods: Patients with RP were randomly divided into a treated group receiving oral nilvadipine at 4 mg/day for ≧30 months and a control group receiving tocopherol nicotinate at 300 mg/day, helenien at 15 mg/day or no medication for the same periods. Progression of RP was evaluated using the 10-2 SITA Fast Program of the Humphrey Visual Field Analyzer, and regression coefficients calculated from the time courses of mean deviation (MD slope) were compared between groups. Results: Nineteen patients in the treated group and 14 patients in the control group completed the follow-up for ≧30 months. The mean (±standard deviation) duration of observation was 48.8 ± 11.8 months (median 48 months, range 30–66 months) for the treated group and 49.2 ± 18.1 months (median 48 months, range 30–90 months) for the control group (p = 0.94). Mean (±standard error of the mean, SEM) regression coefficients of the averaged MD values for the initial 30 months were –0.35 ± 0.17 dB/year in the treated group and –0.75 ± 0.06 dB/year in the control group (p < 0.01). Mean (±SEM) MD slopes for total observational periods were –0.49 ± 0.17 dB/year in the treated group and –0.89 ± 0.16 dB/year in the control group (mean ± SEM, p = 0.042). Conclusion: Nilvadipine at 4 mg/day significantly retarded progression of central visual field defects in RP in this small patient series.

Clinical Characteristics and Current Therapies for Inherited Retinal Degenerations

“…Identifier: NCT01399515). Some studies in animal models have shown that calcium channel blockers (e.g., diltiazem, nicardipine, nilvadipine, or nifedipine) inhibit photoreceptor degeneration (Frasson et al 1999;Takano et al 2004), and a 30-mo clinical trial recently reported that nilvadipine at 4 mg/d significantly retarded progression of central visual field defects in RP (Nakazawa et al 2011). …”

Optogenetic therapy for retinitis pigmentosa

“…A second approach is to slow the degeneration of photoreceptors and thus slow progression of the disease. [13][14][15][16][17][18] Finally, there are a number of approaches that do not interfere with the intrinsic progression of disease but attempt to restore photosensitivity by creating new photosensors and coupling them to the remaining retinal circuitry. Patients who are legally blind are the key target population of these therapies.…”

Correlation between visual sensitivity loss and years affected for eyes with retinitis pigmentosa

“…On the basis of the results from our previous study, Nakazawa and associates [8] reported that nilvadipine, a calciumchannel blocker, could delay the progression of visual dysfunction in eyes with RP, using the MD slope derived from the Humphrey 10-2 program in the 30-month followup period.…”