What Is Naproxcinod?
Naproxcinod belongs to a unique class of anti-inflammatory drugs known as Cyclooxygenase-Inhibiting Nitric Oxide Donators (CINODs). Naproxcinod is the first drug of the CINOD class. Naproxcinod is being developed by NicOx for the treatment of osteoarthritis.
According to drugmaker NicOx, the goal is "to develop naproxcinod as an effective anti-inflammatory agent with no detrimental effects on blood pressure and good gastrointestinal tolerability and safety."
Is Naproxcinod Available Now?
Naproxcinod is not yet available. The last of three Phase III clinical trials (referred to as the 303 study) was reported in November 2008 and the results are positive. The 303 study results are the final data that will be included in the New Drug Application for naproxcinod which is expected to be filed with the U.S. FDA in mid-2009.
Which Studies Support the Approval of Naproxcinod?
Three phase III clinical trials were conducted to assess the safety and effectiveness of naproxcinod. The studies were referred to as 301, 302, 303.The 301 Study
The 301 study was the first clinical trial in the phase III program for naproxcinod. The 301 was a 13-week trial involving 918 patients with osteoarthritis of the knee. At 120 treatment centers in the United States, study participants were given one of the following: naproxcinod 375 mg twice a day, naproxcinod 750 mg twice a day, naproxen 500 mg twice a day or placebo twice daily.
Naproxcinod showed good overall safety. Fewer patients treated with either dose of naproxcinod experienced adverse events compared to those taking naproxen. Naproxcinod was also found to be effective in terms of WOMAC assessment of pain and function, as well as the patient's own assessment of their disease status.The 302 Study
The 302 was the second pivotal phase III trial for naproxcinod. There were 1020 patients with osteoarthritis of the knee who participated at 150 clinical sites in the United States. The results showed that both doses of naproxcinod were superior to placebo. No safety concerns were related to naproxcinod through 26 weeks in the 302 study. Results showed no negative effect of naproxcinod on blood pressure in the 302 study.The 303 Study
The third and final pivotal phase III trial for naproxcinod, was the 303 study. There were 810 patients with hip osteoarthritis enrolled in this study. Results confirmed that pain and function and the patient's overall rating of their disease status was positively affected by naproxcinod.
Also, the patients treated with the higher dose of naproxcinod showed a very similar blood pressure profile to those on placebo as opposed to naproxen, which was associated with increased blood pressure.
Are There Safety Issues Associated With Naproxcinod?
Naproxcinod (750 mg) has showed good overall safety and tolerability in clinical trials. Naproxcinod (750 mg) exhibited the same gastrointestinal adverse event rate as placebo.
In an extension study, blood pressure remained stable for 52 weeks following the completion of the 301 study. This finding indicates that naproxcinod does not increase blood pressure over time.
Naproxcinod - Signs and symptoms of Osteoarthritis – Phase 3. NicOx. Accessed December 6, 2008.
Third Pivotal Phase 3 Study for NicOx' Naproxcinod Shows Positive Efficacy, Safety, and Blood Pressure Results. MarketWatch. November 24, 2008.