title: A 12-week randomized, double-blind, placebo-controlled multicenter study of choline-stabilized orthosilicic acid in patients with symptomatic knee osteoarthritis.
abstract: The aim of this study was to assess the efficacy of choline-stabilized orthosilicic acid (ch-OSA) in patients with symptomatic knee osteoarthritis (OA).
  
  
  
  In a multicenter, double-blind, placebo-controlled study, 211 patients with knee OA (Kellgren and Lawrence grade II or III) and moderate to moderately severe pain were randomly allocated to ch-OSA or placebo for 12 weeks. The primary outcome was the change in the WOMAC pain subscale from baseline to week 12. Secondary outcomes were changes from baseline to week 12 in WOMAC total, WOMAC stiffness, WOMAC physical function, Subject Global Assessment and levels of cartilage degradation biomarkers C-terminal telopeptide of collagen type II (CTX-II) and cartilage oligomeric matrix protein (COMP). Pre-specified subgroup analyses included the effect of gender.
  
  
  
  A total of 166 (120 women, 46 men) patients were included in the analysis (87 and 79 in the ch-OSA and placebo group, respectively). In the total study population, no differences were observed between the two treatment groups for the different outcomes but significant treatment x gender interactions were found. In men taking ch-OSA, a significant improvement in WOMAC total, WOMAC stiffness and WOMAC physical function as well as a lower increase in biomarker levels of cartilage degradation was observed, but not in women. The change in WOMAC pain showed a similar positive trend in men taking ch-OSA.
  
  
  
  After 12 weeks of treatment, no effect was found of ch-OSA in the total study population on clinical parameters and biomarkers, but a gender interaction was observed. In men, ch-OSA was found effective in reducing symptoms of knee OA, which was associated with a slight but significant reduction of biomarkers that are related to cartilage degradation.
  
  
  
  The study was registered retrospectively: ISRCTN88583133 . Registration date: 2015-10-07.
authors.affiliation: Biomedical Research Institute (BIOMED), Hasselt University, Diepenbeek, Belgium. drpgeusens@gmail.com.|Rheumatology, Maastricht UMC, Maastricht, The Netherlands. drpgeusens@gmail.com.|ReumaClinic, Bretheistraat 149, Genk, 3600, Belgium. drpgeusens@gmail.com.
authors.forename: Piet
authors.initials: P
authors.lastname: Geusens
authors.affiliation: Institute of Rheumatology, Prague, Czech Republic.
authors.forename: Karel
authors.initials: K
authors.lastname: Pavelka
authors.affiliation: , Nábrežie I. Krasku 4782/4, Piešťany, Slovakia.
authors.forename: Jozef
authors.initials: J
authors.lastname: Rovensky
authors.affiliation: ReumaClinic, Bretheistraat 149, Genk, 3600, Belgium.
authors.forename: Johan
authors.initials: J
authors.lastname: Vanhoof
authors.affiliation: Research & Development, Bio Minerals NV, Destelbergen, Belgium.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Demeester
authors.affiliation: Research & Development, Bio Minerals NV, Destelbergen, Belgium.
authors.forename: Mario
authors.identifier: 0000-0001-8546-7053
authors.initials: M
authors.lastname: Calomme
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Antwerp-Wilrijk, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Vanden Berghe
mesh_terms: D000284:Administration, Oral; D000368:Aged; D015415:Biomarkers / Q000032:analysis; D002356:Cartilage / Q000473:pathology; D064236:Cartilage Oligomeric Matrix Protein / Q000032:analysis*; D002794:Choline / Q000008:administration & dosage / Q000627:therapeutic use*; D024043:Collagen Type II / Q000032:analysis*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000188:drug therapy*; D059408:Pain Management / Q000379:methods*; D010147:Pain Measurement; D012737:Sex Factors; D012824:Silicic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D064236:Cartilage Oligomeric Matrix Protein; D024043:Collagen Type II; D012824:Silicic Acid; D002794:Choline
keywords: Cartilage degradation marker; Choline; Choline-stabilized orthosilicic acid; Knee; Osteoarthritis; Silicon; WOMAC