The conclusions of Clemson et al concerning valproic acid are premature

Pharmacological Modulation of the Retinal Unfolded Protein Response in Bardet-Biedl Syndrome Reduces Apoptosis and Preserves Light Detection Ability

“…S12, B and D). Apart from being a historical drug used to treat epilepsy in human patients (46), VPA was recently used in a trial of retinitis pigmentosa patients with mutations in the Rhodopsin gene (47)(48)(49). Although VPA-treated patients had a larger visual field than untreated patients in the first study, controversy arose because of inefficiency for other patients and a lack of mechanistic insight on how the VPA protected against apoptosis.…”

Pharmacological approaches to retinitis pigmentosa: A laboratory perspective

“…This finding, however, received some criticism by Sandberg et al, for the criteria used for choosing the appropriate controls (Sandberg et al, 2011;van Schooneveld et al, 2011). Controversial effects on the actions of VPA on small groups of RP patients (Sisk, 2012) indicated that only dominant mutations could possibly benefit from the treatment with this drug.…”

Long-term follow-up for efficacy and safety of treatment of retinitis pigmentosa with valproic acid

“…More recently, after a transition in faculty and change in practice patterns at this institution, any patients currently seen at the University of Florida who had not already self-terminated use of VPA were asked to stop this drug until the release of prospective data on safety and efficacy. In response to criticisms that the findings reported by the previous investigator were premature,18 we wanted to further investigate and provide long-term follow-up on all of the patients at our institution who had been offered off-label use of VPA for various retinal dystrophies, including patients whose findings after short duration treatment had been previously reported 12. After obtaining institutional review board approval, we conducted a retrospective chart review of all patients with retinal dystrophies who had been prescribed VPA at the University of Florida Ophthalmology Department clinic between January 2009 and April 2012.…”