Efficacy of valproic acid for retinitis pigmentosa patients: a pilot study

Abstract

PurposeThe purpose of this study was to examine the efficacy and safety of valproic acid (VPA) use in patients with retinitis pigmentosa (RP).Patients and methodsThis was a prospective, interventional, noncomparative case study. In total, 29 eyes from 29 patients with RP whose best-corrected visual acuities (BCVAs) in logarithm of the minimum angle of resolution (logMAR) ranged from 1.0 to 0.16 with visual fields (VFs) of ≤10° (measured using Goldmann perimeter with I4) were recruited. The patients received oral supplementation with 400 mg of VPA daily for 6 months and were followed for an additional 6 months. BCVAs, VFs (measured with the Humphrey field analyzer central 10-2 program), and subjective questionnaires were examined before, during, and after the cessation of VPA supplementation.ResultsThe changes in BCVA and VF showed statistically significant differences during the internal use of VPA, compared with after cessation (P=0.001). With VPA intake, BCVA in logMAR significantly improved from baseline to 6 months (P=0.006). The mean deviation value of the VF significantly improved from baseline to 1 month (P=0.001), 3 months (P=0.004), and 6 months (P=0.004). These efficacies, however, were reversed to the baseline levels after the cessation of VPA intake. There were no significant relations between the mean blood VPA concentrations of each patient and the changes in BCVA and VF. During the internal use of VPA, 15 of 29 patients answered “easier to see”, whereas blurred vision was registered in 21 of 29 patients on cessation. No systemic drug-related adverse events were observed.ConclusionWhile in use, oral intake of VPA indicated a short-term benefit to patients with RP. It is necessary to examine the effect of a longer VPA supplementation in a controlled study design.

Learning to see again: biological constraints on cortical plasticity and the implications for sight restoration technologies

“…The use of valproate to target visual cortical plasticity is complicated by its adverse side effects (Sandberg et al 2011, Sisk 2012, Bhalla et al 2013) and a literature leaving it unclear whether its effect on retinal function in patients with retinal dystrophies is positive (Clemson et al 2011, Iraha et al 2016) or negative (Sisk 2012, Bhalla et al 2013). …”

Learning to See Again: Biological Constraints on Cortical Plasticity and the Implications for Sight Restoration Technologies

“…As far as epigenetic limitations are concerned, in humans, valproate has been successfully used to enhance auditory cortex plasticity for training in pitch perception in adult humans (Gervain et al 2013), although these findings have yet to be replicated and might not generalize to the visual system. The use of valproate to target cortical plasticity is complicated by its adverse side effects (Sandberg et al 2011, Sisk 2012, Bhalla et al 2013) and a literature leaving it unclear whether its effect on retinal function in patients with retinal dystrophies is positive (Clemson et al 2011, Iraha et al 2016 or negative (Sisk 2012, Bhalla et al 2013.…”

Postępowanie w zwyrodnieniu barwnikowym siatkówki – przegląd piśmiennictwa

“…W postępowaniu farmakologicznym rozważano suplementację niektórych witamin, takich jak A i E [9,10], kwasu dokozaheksagenowego (docosahexaenoic acid -DHA) [3,10,11,12], luteiny [13,14], kwasu walproinowego [15,16], beta-karotenu [17], a także zastosowanie miejscowego podawania 0,2% winianu brimonidyny [18], wszczepianie wewnątrzgałkowych implantów [19] czy doustne przyjmowanie nilwadypiny [20]. Nadzieję wiąże się także z terapią genową [21,22,23] i transplantacją komórek macierzystych [21,23,24,25,26].…”

“…Iraha i wsp. [16] 29 pacjentom z RP podawali 400 mg/d kwasu walproinowego przez 6 miesięcy, a następnie suplementację tę wstrzymali na 6 kolejnych miesięcy. Stwierdzili oni statystycznie istotną poprawę ostrości wzroku i pola widzenia podczas przyjmowania kwasu walproinowego w porównaniu z okresem zaprzestania jego suplementacji.…”