ABSTRACT: BACKGROUND:An intravenous (IV) formulation of meloxicam was developed for moderate-to-severe pain management. This study evaluated the safety and efficacy of meloxicam IV after open abdominal hysterectomy. Meloxicam IV is an investigational product not yet approved by the US Food and Drug Administration. METHODS:Women (N = 486) with moderate-to-severe pain after open abdominal hysterectomy were enrolled in this multicenter, randomized, double-blind, placebo- and active-controlled trial. Subjects were randomized to receive a single dose of meloxicam IV (5-60 mg), placebo, or morphine (0.15 mg/kg) in ?6 hours after morphine dosing on postoperative day 1 and were evaluated for 24 hours. Rescue morphine (?0.15 mg/kg IV) was available if needed for pain not relieved by the study medication. In an open-label extension (N = 295), meloxicam IV was administered once daily for the remaining hospital stay (or per the investigator's discretion). The coprimary efficacy end points were the summed pain intensity difference (SPID24) and total pain relief (TOTPAR24) from hour 0 to 24 hours after dosing. Effect size, the standardized difference between means reported in standard deviation (SD) units, was calculated to indicate the magnitude of the difference in the mean analgesic effect measured for different intervention groups. RESULTS:Subjects who received morphine or meloxicam IV had a median time to first perceptible pain relief within 6-8 minutes. Morphine and meloxicam IV 5-60 mg produced statistically significant differences than placebo in SPID24 and TOTPAR24. SPID24 (standard error [SE]) for meloxicam IV 5-60 mg ranged from -56276.8 (3926.46) to -33517.1 (3930.1; P < .001); SPID24 (SE) for morphine and placebo were -29615.8 (3869.2; P < .001) and 4555.9 (3807.1), respectively. SPID24 effect sizes (95% confidence intervals) for the 60, 30, 15, 7.5, and 5 mg meloxicam IV doses and morphine were 1.93 (1.61-2.25), 2.00 (1.65-2.35), 1.70 (1.35-2.05), 1.28 (0.95-1.60), 1.25 (0.90-1.61), and 1.12 (0.77-1.45) SDs, respectively. TOTPAR24 (SE) for meloxicam IV 5-60 mg ranged from 3104.5 (155.28) to 4130.4 (191.17; P < .001); TOTPAR24 (SE) for morphine and placebo were 2723.3 (188.4; P < .001) and 1100.6 (185.4), respectively. TOTPAR24 effect sizes (95% confidence interval) for the 60, 30, 15, 7.5, and 5 mg meloxicam IV doses and morphine were 2.03 (1.70-2.35), 2.05 (1.70-2.40), 1.78 (1.43-2.13), 1.35 (1.03-1.67), 1.37 (1.01-1.72), and 1.10 (0.75-1.45) SDs, respectively. The mean total opioid consumed (SD) during the double-blind phase was 4.6 (8.17), 5.3 (8.85), 5.9 (7.85), 8.5 (9.67), 9.3 (9.47), 9.6 (8.12), and 16.0 (10.15) mg for patients in the 60, 30, 15, 7.5, and 5 mg meloxicam IV, morphine, and placebo groups, respectively. Generally, meloxicam IV was well tolerated, evidenced by the incidence of adverse events compared to placebo and lack of deaths and treatment-related serious adverse events. CONCLUSIONS:A meloxicam IV dose of 5-60 mg was generally well tolerated and appeared to reduce opioid consumption in subjects with moderate-to-severe pain after open abdominal hysterectomy. Once-daily administration of meloxicam IV produced analgesic effect within 6-8 minutes postdose that was maintained over a 24-hour dosing interval.