Long-term up to 24-month efficacy and safety of concomitant prescription omega-3-acid ethyl esters and simvastatin in hypertriglyceridemic patients.

Objective: Assess the long-term efficacy and safety of prescription omega-3-acid ethyl esters (P-OM3) coadministered with simvastatin in an extension of the Combination of Prescription Omega-3 Plus Simvastatin (COMBOS) trial.

Methods: COMBOS included hypertriglyceridemic patients (triglyceride [TG] >or=200 mg/dL and <500 mg/dL or >or=2.26 mmol/L and <5.64 mmol/L) with low density lipoprotein cholesterol (LDL-C) level no greater than 10% above the National Cholesterol Education Program, Adult Treatment Panel III treatment goal. After an 8-week lead-in phase with simvastatin 40 mg/day (which continued throughout the trial), subjects were randomized to 8 weeks of P-OM3 4 g/day or placebo. Completers were eligible to participate in a 24-month extension study. Those who received placebo + simvastatin in COMBOS switched to open-label P-OM3 + simvastatin ('Switchers'); those who received P-OM3 + simvastatin during COMBOS continued the same regimen (open-label) in the extension phase ('Non-switchers'). The primary endpoint was the difference between Non-switchers and Switchers in median percent change in non-high-density lipoprotein-cholesterol (non-HDL-C) from COMBOS end of treatment to Month 4 of the extension phase.

Results: At Month 4 from COMBOS end of treatment, non-HDL-C was reduced by a median of 9.4% in Switchers and increased by 0.9% in Non-switchers (p < 0.001). For the total population (combined Non-switcher + Switcher population), the median percent change from COMBOS baseline to Months 4, 12, and 24 was -8.3%, -7.3%, and -8.9%, respectively (all p < 0.001). This extension study revealed no unexpected safety findings. A limitation of this study was a gap between completion of COMBOS and enrollment in the extension phase for some patients; however, a post-hoc non-HDL-C sensitivity analysis performed at the 4-month primary endpoint revealed no influence of gap on study results.

Conclusions: In this 24-month extension study, P-OM3 was generally well tolerated, and produced sustained reductions in non-HDL-C levels in simvastatin-treated patients with TG levels between 200 and 500 mg/dL (2.26 mmol/L and 5.64 mmol/L).

Clinical Trial Registry Number: NCT00903409.