A Comparative Analysis of the Efficacy and Safety of Nimesulide/Paracetamol Fixed-Dose Combination With Other NSAIDs in Acute Pain Management: A Randomized, Prospective, Multicenter, Active-Controlled Study (the SAFE-2 Study).

Objective In this study, we aimed to compare the efficacy and safety of the fixed-dose combination (FDC) of nimesulide (100 mg) + paracetamol (325 mg) [NP], ketorolac (10 mg) [Kt] alone, diclofenac (50 mg) + paracetamol (325 mg) [DP], and aceclofenac (100 mg) + paracetamol (325 mg) [AP] in patients with acute painful conditions. Methods This was a randomized, prospective, open-label, multicentre, active-controlled study involving patients aged ≥18 years, with acute painful conditions like low back pain, acute musculoskeletal disorders, and trauma such as tendinitis, tenosynovitis, bursitis, sprains and strains, migraine, dental pain, painful dental procedures, and post-surgical pain. Reduction in pain intensity and liver, renal, gastrointestinal, and cardiovascular safety were assessed on days seven and 14. Results A total of 600 patients were randomized into NP, Kt, DP, and AP groups in a 1:1:1:1 ratio. NP, DP, and AP were administered twice a day while Kt was given three times a day. The reduction of pain as measured by the numerical rating scale (NRS) scores at the end of day seven was 3.75 ± 1.58 in the NP group, 2.96 ± 1.18 in the Kt group, 3.42 ± 1.42 in the DP group, and 3.47 ± 1.30 in the AP group. The pain reduction in the NP group was significantly greater (p<0.001) as compared to the Kt group and non-inferior to the DP and AP groups on days seven and 14. Non-inferiority was concluded between the NP, DP, and AP groups as the lower limit of 95% CI of the difference in the change of pain intensity on both days seven and 14 was above the predefined margin of -1.0. All the drugs were well tolerated, but a significantly greater number of adverse events were reported in the DP group (32) as compared to the NP group (14) (p<0.05). The most common adverse events reported during the study were nausea, gastritis, and abdominal pain in all four groups. There was no significant alteration in liver and renal function tests except a rise in serum creatinine in the DP group. Conclusions The FDC of nimesulide with paracetamol is superior to ketorolac and non-inferior to the FDC of diclofenac with paracetamol and aceclofenac with paracetamol in the management of pain in patients with acute painful conditions. The tolerability profile of the FDC of nimesulide with paracetamol is similar to that of ketorolac but better than diclofenac with paracetamol and aceclofenac with paracetamol combinations.