Study of Heart and Renal Protection

The SHARP (Study of Heart and Renal Protection) was a double-blind placebo-controlled trial which aimed to assess the safety and efficacy of reducing LDL cholesterol in more than 9,000 patients with chronic kidney disease (about 3,000 of whom were on dialysis at randomization).

Patients were randomly assigned to simvastatin 20 mg plus ezetimibe 10 mg daily versus matching placebo (a subset of these patients had previously received simvastatin 20mg only and were then randomly re-assigned to receive simvastatin 20mg plus ezetimibe 10mg or placebo at one year). Details of the SHARP trial design and methods have been reported previously (reference: Am Heart J 2010; 160:785-94.).

SHARP was overseen by an independent Steering Committee that included nephrologists, cardiologists, clinical trialists, and statisticians, with 2 non-voting observers from the main funder (Merck/Schering-Plough Pharmaceuticals). The independent sponsor was the University of Oxford, and the trial was funded by Merck/Schering-Plough Pharmaceuticals, the Australian National Health and Medical Research Council, the British Heart Foundation and the UK Medical Research Council.

In October 2009, the Steering Committee decided (blind to the effects of study treatment on clinical outcomes) to change the original protocol-specified primary outcome to a revised key outcome of major atherosclerotic events, defined as the combination of non-fatal myocardial infarction, coronary death, ischemic stroke, or any revascularization procedure (i.e. exclusion of non-coronary cardiac deaths and strokes confirmed to be hemorrhagic from the original major vascular event outcome). These and other changes are described in the revised statistical analysis plan for SHARP (reference: Am Heart J 2010; 160:785-94.). Accordingly, the chief emphasis of the published results (reference: Lancet 2011; 377:2181-92) is on the revised pre-specified key outcome of first major atherosclerotic events.

Inclusion criteria

• History of chronic kidney disease (CKD): either patients who are pre-dialysis (with a plasma or serum creatinine greater than or equal to 150 micromol/l [greater than or equal to 1.7 mg/dl] in men, or greater than or equal to 130 micromol/l [greater than or equal to 1.5 mg/dl] in women); or patients on dialysis (hemodialysis or peritoneal dialysis)
• Men or women aged greater than or equal to 40 years

Exclusion criteria

• Definite history of myocardial infarction or coronary revascularization procedure
• Functioning renal transplant, or living donor-related transplant planned
• Less than 2 months since presentation as an acute uraemic emergency (but could be entered later, if appropriate)
• Definite history of chronic liver disease, or abnormal liver function (i.e. alanine aminotransferase [ALT] greater than 1.5 x upper limit of normal [ULN] or, if ALT not available, aspartate aminotransferase [AST] greater than 1.5 x ULN). (Note: Patients with a history of hepatitis were eligible provided these limits were not exceeded.)
• Evidence of active inflammatory muscle disease (e.g. dermatomyositis, polymyositis), or creatine kinase (CK) greater than 3 x ULN
• Definite previous adverse reaction to a statin or to ezetimibe
• Concurrent treatment with a contraindicated drug. (Note: Patients who were temporarily taking such drugs could have been re-screened for participation in the study when they discontinued them, if appropriate.) These contraindicated drugs included: HMG-CoA reductase inhibitor ("statin"); fibric acid derivative ("fibrate"); nicotinic acid; macrolide antibiotic (erythromycin, clarithromycin); systemic use of imidazole or triazole antifungals (e.g. itraconazole, ketoconazole); protease-inhibitors (e.g. antiretroviral drugs for HIV infection); nefazodone; ciclosporin
• Child-bearing potential (i.e. premenopausal woman who was not using a reliable method of contraception)
• Known to be poorly compliant with clinic visits or prescribed medication
• Medical history that might have limited the individual's ability to take trial treatments for the duration of the study (e.g. severe respiratory disease, history of cancer other than non-melanoma skin cancer, or recent history of alcohol or substance misuse)