Rationale, Design, and Baseline Clinical Characteristics of the Ziltivekimab Cardiovascular Outcomes Trial

Importance: Cardiovascular inflammation is a major determinant of atherosclerotic disease, and inhibition of the central signaling cytokine, interleukin 6 (IL-6), is a promising target for intervention. Patients with chronic kidney disease (CKD) commonly have plasma elevations of inflammatory biomarkers, such as high-sensitivity C-reactive protein (hsCRP) and IL-6, and are at high risk for life-threatening atherosclerotic events as well as loss of kidney function and might therefore benefit from IL-6 inhibition. Observations: The Ziltivekimab Cardiovascular Outcomes Trial (ZEUS; NCT05021835) will determine the safety and efficacy of IL-6 inhibition with ziltivekimab among patients with atherosclerotic cardiovascular disease (ASCVD), CKD, and systemic inflammation. ZEUS is a multinational, double-blind, placebo-controlled, event-driven, randomized clinical trial inclusive of 6376 participants with ASCVD, CKD, and an hsCRP level greater than or equal to 2 mg/L who were randomized in a 1:1 fashion to receive either ziltivekimab, 15 mg, administered subcutaneously every month or matching placebo. At randomization, mean age was 69.5 years, 27.5% were female, 92.0% had hypertension, 65.7% had diabetes, and 41.3% had heart failure. At baseline, the mean estimated glomerular filtration rate (eGFR) was 44.5 mL/min/1.73 m2, mean low-density lipoprotein cholesterol level was 77.7 mg/dL, median hsCRP level was 4.5 mg/L, and median IL-6 level was 4.9 pg/mL. At enrollment, sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists were being used by 36.8% and 11.3% of the cohort, respectively. The primary outcome is 3-point major adverse cardiovascular events. Secondary cardiovascular outcomes include (1) an expanded major adverse cardiovascular event outcome including hospitalization for unstable angina requiring urgent coronary revascularization, (2) hospitalizations for heart failure or urgent heart failure visits or cardiovascular death, and (3) all-cause mortality. The secondary kidney outcome is a composite of greater than 40% decline in eGFR, eGFR less than 15 mL/min/1.73 m2, dialysis, kidney transplant, death from kidney disease, or cardiovascular death. Conclusions and Relevance: The ZEUS randomized clinical trial will formally test the hypothesis that IL-6 inhibition with ziltivekimab will lower incident cardiovascular event rates and potentially slow kidney decline among participants with known ASCVD, CKD, and elevated hsCRP. If successful, the ZEUS trial would provide a fully novel approach for prevention of myocardial infarction, stroke, cardiovascular death, and kidney function decline among high-risk patients with CKD.