title: Therapeutic potential of valproic acid for retinitis pigmentosa.
abstract: OBJECTIVE
  To examine the efficacy and safety of valproic acid (VPA) in patients with retinitis pigmentosa (RP).
  
  
  METHODS
  Thirteen eyes were examined before and after brief treatment (average 4 months) with VPA. Visual fields (VF) for each eye were defined using digitised Goldmann Kinetic Perimetry tracings. VF areas were log-transformed and VF loss/gain relative to baseline was calculated. Visual acuity was measured using a Snellen chart at a distance of 20&emsp14;feet (6.1 m). Values were converted to the logarithm of the minimum angle of resolution (logMAR) score.
  
  
  RESULTS
  Nine eyes had improved VF with treatment, two eyes had decreased VF and two eyes experienced no change, with an overall average increase of 11%. Assuming typical loss in VF area without treatment, this increase in VF was statistically significant (p<0.02). An average decrease (0.172) in the logMAR scores was seen in these 13 eyes, which translates to a positive change in Snellen score of approximately 20/47 to 20/32, which was significant (p<0.02) assuming no loss in acuity without treatment. Side effects were mild and well tolerated.
  
  
  CONCLUSIONS
  Treatment with VPA is suggestive of a therapeutic benefit to patients with RP. A placebo-controlled clinical trial will be necessary to assess the efficacy and safety of VPA for RP rigorously.
authors.affiliation: Department of Ophthalmology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Clemson
authors.forename: R
authors.initials: R
authors.lastname: Tzekov
authors.forename: M
authors.initials: M
authors.lastname: Krebs
authors.forename: J M
authors.initials: JM
authors.lastname: Checchi
authors.forename: C
authors.initials: C
authors.lastname: Bigelow
authors.forename: S
authors.initials: S
authors.lastname: Kaushal
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012174:Retinitis Pigmentosa / Q000188:drug therapy* / Q000235:genetics / Q000503:physiopathology; D012189:Retrospective Studies; D016896:Treatment Outcome; D014635:Valproic Acid / Q000627:therapeutic use*; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests; D014801:Vitamin A / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D014801:Vitamin A; D014635:Valproic Acid