[Efficacy Survey of Naldemedine in the Poor-performance Status Group]

Safety of Naldemedine for Opioid-Induced Constipation - A Systematic Review and Meta-Analysis

Naldemedine is a peripheral acting µ-opioid receptor antagonist approved by the Food and Drug Administration to treat opioid-induced constipation. Concerns about side effects like opioid withdrawal prevent its widespread use, especially for cancer patients. We performed this systematic review and meta-analysis to evaluate existing safety data of naldemedine treating opioid-induced constipation following the PRISMA guidelines. We searched PubMed and the Cochrane Library on April 16th 2024 to identify studies evaluating naldemedine treatment among patients with opioid-induced constipation. Our analysis found no differences between groups comparing naldemedine therapy with placebo-control for treatment-emergent adverse events (OR = 1.06; 95%-CI: 0.91-1.24), serious adverse events (OR = 1.02; 95%-CI: 0.76-1.38). We found no increased risk for opioid withdrawal, while an increased risk for gastrointestinal disorders (OR = 2.08; 95%-CI: 1.72-2.51), particularly higher incidences of diarrhea (OR = 2.44; 95%-CI: 1.81-3.29) and abdominal pain (OR = 3.31; 95%-CI: 2.16-5.06) were found. In the cancer subgroup, treatment-emergent and serious adverse events were more frequent. However, no increased risk for opioid withdrawal was observed. This analysis confirms naldemedine's overall safety in treating opioid-induced constipation, with manageable gastrointestinal side effects. However, the higher adverse events in cancer patients require further investigation to ensure safe use in this population.

A Retrospective Observational Study of Factors Affecting the Efficacy of Concurrent Prescription of Naldemedine for Opioid-Induced Constipation Caused by Oxycodone Tablets

Naldemedine is indicated for the treatment of opioid-induced constipation (OIC), but reports on its efficacy in preventing OIC are few. Therefore, we retrospectively investigated factors affecting the efficacy of concurrent prescription of naldemedine on OIC. Outpatients with cancer who were started on oxycodone 10 mg/d were included in the study. The eligible patients were classified by their physicians into the following three groups: Group A used regular laxatives before the introduction of oxycodone and initiated naldemedine treatment simultaneously with oxycodone administration, Group B did not take laxatives before the introduction of oxycodone and started naldemedine simultaneously with oxycodone administration, and Group C had been administering regular laxatives before the introduction of oxycodone and were not prescribed naldemedine simultaneously with oxycodone treatment. The Support Team Assessment Schedule Japanese edition score for constipation, frequency of defecation, Bristol Stool Form Scale, sense of incomplete rectal evacuation, and development or worsening of straining to pass bowel movements were compared among the three groups before and after oxycodone administration. In Group B, there was significant worsening of the four parameters except for the sense of incomplete rectal evacuation, whereas Groups A and C did not present any changes. In logistic regression analysis, body weight ≥51.8 kg was a factor significantly decreasing the preventive effect of naldemedine on OIC, and regular use of laxatives was a factor significantly increasing the preventive effect of naldemedine on OIC. Thus, the initiation of naldemedine should be considered depending on the body weight and regular laxative use.