title: A randomized placebo-controlled pilot study of the efficacy and safety of D-cycloserine in people with chronic back pain.
abstract: Few effective pharmacological treatment options exist for chronic back pain, the leading cause of disability in the US, and all are associated with significant adverse effects.
  
  
  
  To determine the efficacy and safety of D-cycloserine, a partial agonist to the N-methyl-D-aspartate receptor, in the treatment of chronic low back pain.
  
  
  
  A total of 41 participants with chronic back pain who met all inclusion and exclusion criteria were enrolled in a double-blind, placebo-controlled randomized pilot trial of D-cycloserine. Treatment was administered orally for six weeks at escalating daily doses of 100 mg, 200 mg, and 400 mg, each for two weeks. The primary outcome measure was back pain intensity using the Numeric Rating Scale (0-10). Secondary measures were back pain-related questionnaires: McGill Pain Questionnaire short form, painDETECT, PANAS, and BDI. The pre-specified analysis was a two-way repeated measures analysis of variance.
  
  
  
  A treatment difference was observed between groups treated with D-cycloserine and placebo at six weeks of 1.05 ± 3.1 units on the Numeric Rating Scale, with an effect size of 0.4 and p = 0.14. This trend of better chronic back pain relief with D-cycloserine was also observed in the secondary measures. No safety issues were seen.
  
  
  
  The difference in mean pain between the D-cycloserine and placebo groups did not reach statistical significance. However, a clinically meaningful effect size in the magnitude of pain relief was observed with a consistent pattern across multiple outcome measures with good safety, supporting further research into the effectiveness of D-cycloserine for chronic back pain.
authors.affiliation: Department of Physical Medicine and Rehabilitation and Division of Rheumatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA tjs@northwestern.edu.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Schnitzer
authors.affiliation: Department of Psychiatry, University of Virginia School of Medicine, VA, USA.
authors.forename: Souraya
authors.initials: S
authors.lastname: Torbey
authors.affiliation: Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Kristi
authors.initials: K
authors.lastname: Herrmann
authors.affiliation: Jefferson School of Pharmacy, Thomas Jefferson University, PA, USA.
authors.forename: Gagan
authors.initials: G
authors.lastname: Kaushal
authors.affiliation: Department of Physical Medicine and Rehabilitation and Division of Rheumatology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: Renita
authors.initials: R
authors.lastname: Yeasted
authors.affiliation: Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
authors.forename: A
authors.initials: A
authors.lastname: Vania Apkarian
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D059350:Chronic Pain / Q000188:drug therapy*; D003523:Cycloserine / Q000009:adverse effects* / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods; D010865:Pilot Projects; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D016194:Receptors, N-Methyl-D-Aspartate; D003523:Cycloserine
keywords: D-cycloserine; N-methyl-D-aspartate agonist; chronic back pain; clinical trial; randomized