Efficay and tolerability of meloxicam, a COX-2 preferential nonsteroidal anti-inflammatory drug: a review

Meloxicam is an enolcarboxamide with preferential COX-2 inhibitory activity. In vitro studies with human tissues have confirmed the high affinity of meloxicam for COX-2, whereas COX-1 was inhibited only at the highest concentrations (ratio of 50% inhibitory concentration for COX-2 : COX-1 = 0.09 in whole blood assays).Meloxicam has a bioavailability of 89% after oral administration, is strongly bound to plasma proteins, and its half-life is 20-24 hours. It readily penetrates into synovial fluid, reaching 45-57% of plasma concentrations. Meloxicam pharmacokinetics are not significantly altered in elderly patients or in those with mild renal/hepatic impairment. The efficacy and tolerability of meloxicam in the treatment of pain and inflammation associated with rheumatic and musculoskeletal disorders has been evaluated in numerous studies comparing meloxicam 7.5-15 mg/day (up to 22.5 mg/day in ankylosing spondylitis), administered for 2 weeks to 12 months, with placebo or other nonsteroidal anti-inflammatory drugs (NSAIDs). Overall, the efficacy of meloxicam was significantly superior to that of placebo and similar to that of other NSAIDs, whereas the incidence of adverse events (especially gastrointestinal) was lower than with other NSAIDs. Intramuscular meloxicam provided faster pain relief than the oral drug in patients with rheumatoid arthritis. Meloxicam also appears to be effective in the prevention of postoperative pain, as shown in patients undergoing abdominal hysterectomy or inguinal hernia repair. Meloxicam may also have a cardioprotective role: in patients with acute coronary syndrome without ST-segment elevation, a lower incidence of cardiovascular events was observed in those who received meloxicam plus aspirin and heparin versus aspirin and heparin alone, both during coronary care stay and at 90-day follow-up. Meloxicam has demonstrated a favourable tolerability profile in large-scale comparative trials, where its gastrointestinal tolerability was superior to that of nonselective NSAIDs. In particular, meloxicam 7.5 mg/day was associated with a lower incidence of gastrointestinal adverse events compared with diclofenac (13% vs 19%; p < 0.001) or piroxicam (10.3% vs 15.4%; p < 0.001). This was confirmed by a prescription-event monitoring study that found a relatively low incidence of dyspepsia, upper gastrointestinal haemorrhage and peptic ulcer (28.3, 0.4 and 0.3 per 1000 patient-months, respectively) among first-time users of meloxicam. In conclusion, meloxicam is at least as effective as nonselective NSAIDs in the treatment of rheumatic disease or postoperative pain, but has a more favourable gastrointestinal tolerability profile. Further investigations into the potential role of meloxicam as a cardioprotective agent are warranted.