Pilot study of oral polymeric N-acetyl-D-glucosamine as a potential treatment for patients with osteoarthritis

Clin Ther. Nov-Dec 1996;18(6):1184-90. doi: 10.1016/s0149-2918(96)80073-7.


Glucosamine and its derivatives, such as glucosamine sulfate and N-acetyl-D-glucosamine (NAG), have been shown to be effective in the treatment of patients with osteoarthritis. Unfortunately, the half-life of glucosamine in the blood is relatively short; therefore, a sustained-release form of the compound would be highly desirable. The purpose of this pilot study was to determine whether the polymeric form of NAG (POLY-Nag) could provide a longer-lasting oral source of NAG. Ten healthy subjects each ingested 1 g/d of either NAG or POLY-Nag for 3 days. After a 4-day washout period, each subject was crossed over to receive the other compound for 3 days. Serum samples were collected and analyzed using high-performance liquid chromatography. Results show that orally ingested NAG and POLY-Nag are absorbed, resulting in increased serum levels of NAG, and POLY-Nag appears to be at least as effective as NAG. Serum levels of NAG had decreased by 48 hours after cessation of ingestion of NAG or POLY-Nag but were still above baseline levels. Increases in serum glucosamine levels indicate that NAG and POLY-Nag are converted to glucosamine in vivo. In conclusion, POLY-Nag may provide a source of serum glucosamine for treatment of patients with osteoarthritis. Longer and more rigorous pharmaco-kinetic and clinical studies need to be done.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorption
  • Acetylglucosamine / pharmacokinetics
  • Acetylglucosamine / therapeutic use*
  • Administration, Oral
  • Adult
  • Chromatography, High Pressure Liquid
  • Cross-Over Studies
  • Female
  • Follow-Up Studies
  • Glucosamine / pharmacokinetics
  • Glucosamine / therapeutic use
  • Half-Life
  • Humans
  • Male
  • Middle Aged
  • Osteoarthritis / blood
  • Osteoarthritis / drug therapy*
  • Pilot Projects
  • Polymers / pharmacokinetics
  • Polymers / therapeutic use
  • Reference Values
  • Treatment Outcome


  • Polymers
  • Glucosamine
  • Acetylglucosamine