Ketoprofen extended-release capsules: a new formulation for the treatment of osteoarthritis and rheumatoid arthritis.

Ketoprofen is a nonsteroidal anti-inflammatory drug (NSAID) of the propionic acid family with demonstrated efficacy in the treatment of rheumatoid arthritis and osteoarthritis; a distinguished safety profile; and good tolerability. This report describes a new extended-release formulation that maintains therapeutic plasma ketoprofen concentrations for up to 24 hours. A single 200-mg capsule thus provides daytime and nighttime symptom control. Small pellets, enclosed in a gelatin capsule, are released in the stomach but release their contained ketoprofen only after reaching the nonacidic environment of the small intestine. Diurnal fluctuations in plasma concentrations of ketoprofen are reduced, and the drug does not accumulate in plasma with extended use. The half-life of the drug from this dosage form is not significantly affected by the increasing age of the patients. The efficacy of extended-release ketoprofen in British clinical trials has been comparable to that of conventional ketoprofen or naproxen. Safety profiles have been comparable to profiles of other NSAIDs; adverse effects have usually been mild and transient, although, as with other NSAIDs, ulcers and bleeding can occur. Extended-release ketoprofen appears to be a good choice for the symptomatic treatment of rheumatoid arthritis and osteoarthritis. Convenient once-daily administration may help improve patients' compliance.