The Efficacy and Safety of Pelubiprofen in the Treatment of Acute Upper Respiratory Tract Infection: A Multicenter, Randomized, Double-Blind, Non-Inferiority Phase III Clinical Trial Compared to Loxoprofen

<b>Background/Objectives:</b> Acute upper respiratory tract infections (URTIs) are common illnesses that cause significant discomfort due to symptoms such as fever, headache, sore throat, and muscle pain. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for symptom relief due to their anti-inflammatory, analgesic, and antipyretic properties. Pelubiprofen, a new NSAID, has not been extensively evaluated for its efficacy and safety in treating URTI-related symptoms, particularly fever. This study aimed to demonstrate that pelubiprofen is not inferior to loxoprofen in reducing fever in patients with URTIs. <b>Methods</b>: This phase III, multicenter, randomized, double-blind, parallel-group, active-controlled, non-inferiority trial involved 181 adults with URTI-related fever (≥38.0 °C), who were randomly assigned to receive pelubiprofen or loxoprofen at a 1:1 ratio. The primary end point was decreasing axillary temperature 4 h post-dose. Secondary end points included fever reduction, pain relief based on the visual analog scale (VAS), and safety. <b>Results:</b> Of the 181 participants, 130 (pelubiprofen [<i>n</i> = 61] and loxoprofen group [<i>n</i> = 69]) underwent randomization. The mean reduction in axillary temperature at 4 h post-dose was comparable between the two groups (-0.08 ± 0.62 °C). The lower bound of the 97.5% one-sided confidence interval was -0.30 °C, which is greater than the non-inferiority margin of 0.35 °C, demonstrating the non-inferiority of pelubiprofen to loxoprofen. The secondary outcomes showed no significant differences in efficacy or safety (<i>p</i> > 0.05). <b>Conclusions</b>: Pelubiprofen is not inferior to loxoprofen in reducing fever associated with URTIs and is a safe and effective treatment option. Registration: (ClinicalTrials.gov identifier: NCT01779271).