Efficacy and Tolerability of Evolocumab vs Ezetimibe in Patients With Muscle-Related Statin Intolerance The GAUSS-3 Randomized Clinical Trial

IMPORTANCE Muscle-related statin intolerance is reported by 5% to 20% of patients. OBJECTIVE To identify patients with muscle symptoms confirmed by statin rechallenge and compare lipid-lowering efficacy for 2 nonstatin therapies, ezetimibe and evolocumab. DESIGN, SETTING, AND PARTICIPANTS Two-stage randomized clinical trial including 511 adult patients with uncontrolled low-density lipoprotein cholesterol (LDL-C) levels and history of intolerance to 2 or more statins enrolled in 2013 and 2014 globally. Phase A used a 24-week crossover procedure with atorvastatin or placebo to identify patients having symptoms only with atorvastatin but not placebo. In phase B, after a 2-week washout, patients were randomized to ezetimibe or evolocumab for 24 weeks. INTERVENTIONS Phase A: atorvastatin (20 mg) vs placebo. Phase B: randomization 2: 1 to subcutaneous evolocumab (420 mg monthly) or oral ezetimibe (10 mg daily). MAIN OUTCOME AND MEASURES Coprimary end points were the mean percent change in LDL-C level from baseline to the mean of weeks 22 and 24 levels and from baseline to week 24 levels. RESULTS Of the 491 patients who entered phase A (mean age, 60.7 [SD, 10.2] years; 246 women [50.1%]; 170 with coronary heart disease [34.6%]; entry mean LDL-C level, 212.3 [SD, 67.9] mg/dL), muscle symptoms occurred in 209 of 491 (42.6%) while taking atorvastatin but not while taking placebo. Of these, 199 entered phase B, along with 19 who proceeded directly to phase B for elevated creatine kinase (N = 218, with 73 randomized to ezetimibe and 145 to evolocumab; entry mean LDL-C level, 219.9 [SD, 72] mg/dL). For the mean of weeks 22 and 24, LDL-C level with ezetimibe was 183.0 mg/dL; mean percent LDL-C change, -16.7%(95% CI, -20.5% to -12.9%), absolute change, -31.0mg/dL and with evolocumab was 103.6 mg/dL; mean percent change, -54.5%(95% CI, -57.2% to -51.8%); absolute change, -106.8 mg/dL (P<.001). LDL-C level at week 24 with ezetimibe was 181.5mg/dL; mean percent change, -16.7%(95% CI, -20.8% to -12.5%); absolute change, -31.2 mg/dL and with evolocumab was 104.1 mg/dL; mean percent change, -52.8%(95% CI, -55.8% to -49.8%); absolute change, -102.9 mg/dL (P<.001). For the mean of weeks 22 and 24, between-group difference in LDL-C was -37.8%; absolute difference, -75.8 mg/dL. Forweek 24, between-group difference in LDL-C was -36.1%; absolute difference, -71.7 mg/dL. Muscle symptoms were reported in 28.8% of ezetimibe-treated patients and 20.7% of evolocumab-treated patients (log-rank P=.17). Active study drug was stopped for muscle symptoms in 5 of 73 ezetimibe-treated patients (6.8%) and 1 of 145 evolocumab-treated patients (0.7%). CONCLUSIONS AND RELEVANCE Among patients with statin intolerance related to muscle-related adverse effects, the use of evolocumab compared with ezetimibe resulted in a significantly greater reduction in LDL-C levels after 24 weeks. Further studies are needed to assess long-term efficacy and safety.