Colesevelam HCl effects on atherogenic lipoprotein subclasses in subjects with type 2 diabetes

Research design and methods: Glucose-Lowering Effect of Welchol Study (GLOWS) was a randomized, double-blind, placebo-controlled trial to examine the effects of colesevelam HCl on glycemic and lipid control in type 2 diabetes patients with HbA1c (A1C) between 7.0% and 10.0%. After a 4-week placebo lead-in period, 65 subjects (31 colesevelam, 34 placebo) were randomized to receive colesevelam 3.75 g/day or matching placebo for 12 weeks in addition to maintaining their previous oral antihyperglycemic regimen (metformin, sulfonylurea, or both). Lipoprotein subclasses measured by nuclear magnetic resonance spectroscopy were secondary efficacy variables evaluated in 56 subjects (26 colesevelam, 30 placebo) at baseline and week 12. Results: Previously published data demonstrated that colesevelam resulted in significant reductions in LDL-C, and Apo B. This analysis demonstrates that relative to placebo, colesevelam treatment reduced mean total LDL particle concentration (LDL-P) by 15.5% (-242 nmol/L [-412, -72], p = 0.006) primarily due to lowering in small LDL-P (-207 nmol/L [-418, 4], p = 0.054) and a lesser reduction in large LDL-P [-30 nmol/L [-118, 58], p = 0.496) and IDL-P (-5 nmol/L [-21, 11], p = 0.557). Conclusions: In type 2 diabetes patients, colesevelam improves glycemic status and reduces the concentration of LDL-C and LDL-P with little change in concentrations of other lipoprotein particles.