A Phase IV Randomized Trial of Maxigesic® Versus Standard Analgesia After Radical Gastrectomy

Background: Radical gastrectomy causes moderate-to-severe pain during the first 48 hours after surgery. Opioids are effective but carry adverse effects and risks of prolonged use, so ERAS-based care recommends multimodal analgesia. Acetaminophen is the most commonly used non-opioid analgesic in gastrectomy patients; adding ibuprofen as a fixed-dose combination has shown improved analgesia and opioid-sparing effects compared with acetaminophen alone in other surgical populations, but direct evidence in gastrectomy patients is limited. Objective: To evaluate whether scheduled administration of an acetaminophen-ibuprofen fixed-dose combination (Maxigesic® IV) is superior to acetaminophen alone for pain relief after radical gastrectomy, with exploratory assessment of cost-effectiveness and of differences in analgesic efficacy according to genetic polymorphisms. Hypothesis: When given on an identical scheduled regimen, the acetaminophen-ibuprofen fixed-dose combination produces significantly lower pain scores (NRS) over the first 48 postoperative hours than acetaminophen alone (superiority). Study plan: This is a phase IV, multicenter, double-blind, randomized controlled trial in which 160 gastric cancer patients scheduled for minimally invasive radical gastrectomy (80 per arm) are randomized 1:1 with stratification by institution. In both arms, the assigned drug is given as a 15-minute intravenous infusion every 6 hours, starting 30 minutes before the end of surgery through 48 hours postoperatively. The primary endpoint is the between-group difference in the time-weighted average (TWA) of repeatedly measured resting and active NRS over 48 hours, analyzed using a mixed model for repeated measures (MMRM); secondary endpoints include opioid consumption (MME), the Quality of Recovery score (QoR-15K), the incidence of chronic postsurgical pain (CPSP), and in-hospital costs.

Sex

All

Minimum age

20 Years

Maximum age

80 Years

Inclusion Criteria:

* Patients aged 20 to 80 years diagnosed with gastric cancer by endoscopic biopsy who are scheduled for minimally invasive radical gastrectomy (laparoscopic or robotic)
* Patients scheduled for distal, proximal, or total gastrectomy among minimally invasive procedures (wedge resection, pylorus-preserving gastrectomy, and segmental gastrectomy are not eligible)
* Patients with an ECOG performance status of 0 or 1 and an ASA classification of I-III
* Patients who have voluntarily agreed to participate after receiving a full explanation of the study's purpose and content, and who have signed the written informed consent form approved by the Institutional Review Board
* Patients residing in Korea who are able to complete follow-up for 3 months after surgery

Exclusion Criteria:

* Patients with a reported history of hypersensitivity, allergy, or adverse reaction to NSAIDs, opioids, or acetaminophen
* Patients currently taking medications that may affect the study results, such as opioid or non-opioid analgesics, aspirin, warfarin or other anticoagulants, steroids, or high-dose hepatotoxic drugs
* Pregnant or breastfeeding patients
* Patients with a contraindication to NSAIDs or acetaminophen identified from medical history or preoperative evaluation-for example, active liver disease, heart failure, chronic kidney disease, thrombocytopenia, or a history of asthma (peptic ulcer disease is not an exclusion criterion)
* Patients unable to read or understand the informed consent form
* Patients weighing less than 45 kg
* Patients scheduled for transfer to the intensive care unit instead of a general ward after surgery (ICU preparation)
* Patients scheduled for emergency surgery