Flare during drug withdrawal as a method to support efficacy in rheumatoid arthritis: amiprilose hydrochloride as an example in a double blind, randomized study

J Rheumatol. 1998 Jan;25(1):30-5.


Objective: To evaluate the use of a randomized, double blind, drug withdrawal design as a means to test the efficacy of longterm therapy with antirheumatic drugs.

Methods: We evaluated 286 patients with rheumatoid arthritis (RA) treated with amiprilose hydrochloride for 1-3 years, with response, with or without other antirheumatic therapy, in a double blind, 12 week withdrawal study that compared patients randomized to continue amiprilose therapy vs patients randomized to placebo. The primary efficacy variable was preventing a predefined degree of clinical reactivation, or flare; the statistical tests of success were a difference in the proportion of flares and in the mean time to flare.

Results: Thirty percent of patients taking amiprilose and 43% of placebo patients experienced flare (p = 0.026). Patients taking amiprilose had a longer flare-free interval compared to placebo patients (p = 0.027), with the time to reactivation or flare becoming statistically different 73 days after withdrawal.

Conclusion: Placebo controlled withdrawal designs are useful as evidence to support the longterm effectiveness of therapy in a proportion of patients with RA.

Publication types

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

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects*
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use
  • Arthritis, Rheumatoid / drug therapy
  • Arthritis, Rheumatoid / etiology*
  • Double-Blind Method
  • Female
  • Glucosamine / adverse effects
  • Glucosamine / analogs & derivatives*
  • Glucosamine / therapeutic use
  • Humans
  • Male
  • Middle Aged
  • Ribose / analogs & derivatives
  • Substance Withdrawal Syndrome / etiology*


  • Anti-Inflammatory Agents, Non-Steroidal
  • Ribose
  • Glucosamine
  • amiprilose