In 2015, oxaprozin was one of twenty NSAIDs included in a clinical trial to compare the efficacy of NSAIDs in the short-term treatment of ankylosing spondylitis. The NSAIDs were compared by completing randomized controlled trials of NSAIDs in patients with active AS. Efficacy reported at 2–12 weeks and adverse effects were examined. Efficacy was measured by change in pain score and change in the duration of morning stiffness. A total of 26 trials with a total of 3410 participants were completed. While all 20 NSAIDs were found to reduce more pain than the placebo, 15 were found to be significantly better. In regards to the decrease of morning stiffness and the likelihood of adverse events, there was no significant difference between NSAIDs. It was concluded that etoricoxib was more effective in reducing pain of AS, however due to small studies and insufficient evidence, no one NSAID could be determined to be the most effective treatment of AS. After etoricoxib, patients taking oxaprozin experienced the least amount of pain with fewer adverse effects than naproxen.
History
Oxaprozin was developed and patented by Wyeth-Ayerst. The US patent 3578671, Oxazoles, was filed November 6, 1967 and published May 11, 1971. Following the filing of the patent, the first description of oxaprozin exhibiting anti-inflammatory properties was outlined in the article Diaryloxazole and diaylthiazolealkanoci acids: two novel series of non-steroidal anti-inflammatory agents. This article was published in Nature in 1968. In December 1988, Wyeth-Ayerst licensed the marketing rights for the US, Canada, Puerto Rico, and the Caribbean to Searle. Daypro became available January 5, 1993. Upon its release, “The Pink Sheet” estimated that the average whole sale price of Searle's Daypro was $112.30 for 100 tablets. The price was comparable to other prescription NSAIDs.
Society and culture
FDA approval
The oxaprozin new drug application was submitted to the FDA on August 10, 1982. The drug was granted an “NDA Day” review on June 15–16, 1992. After Searle agreed to complete seven Phase IV postmarketing studies on October 22, the FDA approved Daypro on October 29, 1992. Since the approval of Daypro by Searle, other companies have submitted abbreviated new drug applications to the FDA. Daypro by Searle is listed as the Reference Listed Drug to prove the bioequivalence of the ANDAs. Below is a table listing all of the approved oxaprozin products.
