INVESTIGATION INTO THE DURATION OF ACTION OF SUSTAINED-RELEASE IBUPROFEN IN OSTEOARTHRITIS AND RHEUMATOID-ARTHRITIS

The duration of action of sustained-release ibuprofen ('Brufen Retard') was investigated in a 14-day double-blind study involving 14 osteoarthritis and 10 rheumatoid arthritis patients. The recommended once-daily dosage of this preparation (1600 mg taken in the evening)provided effective control of arthritic symptoms for both patient groups, with significant overall improvements in pain and stiffness compared to baseline. Substitution of placebo for a single dose of the active treatment resulted in a trend towards worsening of pain and stiffness in the rheumatoid group; however, the only statistically significant change involved impaired quality of sleep (p = 0.03) du ring the night after placebo administration, over 24-hours after the previous dose of active medication. In this particular study, symptom control was also clearly achieved for the osteoarthritis patients, as this group showed no deterioration within the same period The 24-hour clinical action underlying these findings is consistent with ibuprofen plasma profiles obtained with the sustained-release preparation in earlier pharmacokinetic studies. It is likely that the greater sensitivity of rheumatoid patients to withdrawal of a single day's active treatment in this study reflects a more severe inflammatory disease process than that of the osteoarthritis patients.