A DOUBLE-BLIND-STUDY COMPARING THE EFFICACY AND SAFETY OF ENTERIC-COATED NAPROXEN TO NAPROXEN IN THE MANAGEMENT OF NSAID INTOLERANT PATIENTS WITH RHEUMATOID-ARTHRITIS AND OSTEOARTHRITIS

Objective. To compare efficacy and gastrointestinal (GI) tolerability of a new enteric coated formulation of naproxen (NAP-EC) with standard immediate release naproxen (NAP-STD). Methods. One hundred seventy-ni ne patients with osteoarthritis (OA) and one hundred seventy-six patie nts with rheumatoid arthritis (RA) at high risk for developing GI side effects to nonsteroidal antiinflammatory drug (NSAID) therapy were en rolled in a double blind, parallel, multicenter study. All patients ha d either discontinued an NSAID during the previous one year or require d cotreatment with antiulcer drugs for control of GI complaints relate d to NSAID use. The treatments were evenly divided in both diagnostic cohorts. Results. Except for minor differences in alcohol consumption, baseline characteristics of patients in both treatment groups were st atistically similar. Both naproxen formulations were highly efficaciou s by all variables of disease activity when changes were measured from baseline. No statistically significant between formulation difference was found in the primary efficacy variable, overall disease activity. Overall, between formulation differences in efficacy measures were fe w, though most favored NAP-STD, GI complaints were reduced by 15% (51% NAP-EC vs 60% NAP-STD, p = 0.077) and GI complaints thought to be dru g related were reduced by 36% (16% NAP-EC vs 25% NAP-STD, p = 0.024). Withdrawals due to GI complaints were reduced by 37% in the NAP-EC gro up (12% NAP-EC vs 19% NAP-STD, p = 0.054), and withdrawals due to GI c omplaints judged to be drug related were reduced by 55% in the NAP-EC group (6% NAP-EC vs 12% NAP-STD, p = 0.025). Conclusion. Enteric coate d naproxen is an effective treatment for OA and RA. All observed diffe rences in GI tolerability favor NAP-EC over NAP-STD.