Author(s): Leonard J, Baker DE
OBJECTIVE: To describe the effectiveness of naloxegol for the treatment of opioid-induced constipation (OIC) in chronic non-cancer pain patients. DATA SOURCES: Citations in PubMed, Google Scholar, Cochrane Library, CINAHL, ScienceDirect, and ProQuest were obtained. Reference lists from individual articles obtained were reviewed for additional sources. STUDY SELECTION AND DATA EXTRACTION: All English-language publications available as poster presentations, abstracts, and peer-reviewed articles ranging from preclinical to phase III trials and published between 2007 and September 14, 2014, were reviewed and summarized. DATA SYNTHESIS: Naloxegol was shown to be effective for increasing the average weekly number of spontaneous bowel movements (SBMs) in a single phase II trial enrolling 208 patients. Phase III trials (KODIAC-04/-05) enrolling a total of 1352 patients developed a new primary end point with a more strict responder criteria. This entailed a mean increase in SBMs, at least 3 SBMs per week, efficacy in 9 of 12 weeks, and efficacy in 3 of the final 4 weeks of the study period. Both groups receiving naloxegol 25 mg had significant improvement over the placebo group. The improvement was similar in patients who reported failure with laxatives in the past and regardless of daily opioid dose. A long-term trial (KODIAC-08) showed safety over 52 weeks. CONCLUSION: OIC affects many individuals treated with opioids for chronic non-cancer pain. Previous over-the-counter or prescription treatment options were limited by a lack of adequate and well-controlled studies, multiple daily dosing, or need for injections. Cost issues may limit therapy with naloxegol to select patients.