A Trial of Alirocumab and Plaque Regression in Peripheral Arterial Disease

Peripheral Arterial Disease Clinical Trial

Official title:

A Double Blind, Randomized Trial of Alirocumab and Plaque Regression in Peripheral Arterial Disease

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02959047
• Other study ID #: 19404
• Status: Completed
• Phase: Phase 4
• Start date: July 17, 2017
• Est. completion date: May 8, 2023

Study information

• Verified date: May 2023
• Source: University of Virginia
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Peripheral arterial disease (PAD) is characterized by lower limb arterial obstruction due to atherosclerosis. Magnetic resonance imaging (MRI) methods can accurately quantify atherosclerotic plaque in the superficial femoral artery (SFA) in patients with PAD. Such techniques have demonstrated plaque regression with statin therapy over 1 year. Alirocumab is a PCSK9 inhibitor that effectively reduces LDL cholesterol up to 70% in patients on statins or intolerant to statins. The investigators hypothesize that effective low density lipoprotein (LDL) lowering with Alirocumab 150m subcutaneously (SQ) every 2 weeks will regress atherosclerotic plaque in the SFA in patients with PAD over one year compared to placebo. 54 patients with mild-moderate PAD (ankle brachial index or ABI 0.4-0.9) will be randomized to alirocumab 150 mg SQ every 2 weeks or matching placebo at the University of Virginia (UVA) (n=34) and Northwestern (n=20). The primary endpoint is change in atherosclerotic plaque volume in the superficial femoral artery over the 1 year treatment period. Secondary endpoints include changes in peak calf muscle perfusion after thigh cuff occlusion/hyperemia, 6-minute walk distance, and blood biomarkers (LDL cholesterol, fibrinogen, high sensitivity c-reactive protein (hs-CRP), and lipoprotein(a).

Description:

PAD is characterized by lower limb arterial obstruction due to atherosclerosis. There are over 8.5 million people with PAD in the U.S. Recent data in a general population over 40 demonstrated an incidence of PAD defined by ankle brachial index (ABI) of 4.3%. Another study of over 3000 patients, mean age 59, demonstrated a prevalence of 3.9%. The prevalence is age-dependent, rising to 14.5% in those over 70. In populations at risk including diabetics or smokers, the incidence is nearly 30%. Standard cardiovascular (CV) risk factors are also risks for PAD, especially smoking, diabetes, hypertension, African-American race and chronic kidney disease. The annual rate of CV events including myocardial infarction, stroke, and CV death is 5-7%. The adjusted risk of dying of a CV event is 2-fold higher than those without PAD. Magnetic resonance imaging (MRI) methods can accurately quantify atherosclerotic plaque in the superficial femoral artery (SFA) in patients with PAD. These measures can be performed rapidly and reproducibly with an intraclass correlation of 0.997 for intraobserver reproducibility, 0.987 for intraobserver, and 0.996 for test-retest reproducibility, Plaque regression with statins have been shown using these techniques in PAD. Alirocumab is a PCSK9 inhibitor that effectively reduces LDL cholesterol up to 70% in patients on statins or intolerant to statins. This injectable agent has proven safe and well-tolerated, but has not yet been studied specifically in patients with peripheral arterial disease.The study will be a double blind, placebo-controlled, randomized study of Alirocumab vs. placebo in 54 patients with PAD. Baseline visit: Informed consent will be signed. Vital signs will be taken and blood drawn fasting for baseline values. A MRI would be performed with black blood imaging of the SFA of both legs. Approximately 10-15 cm of each leg would be covered, using a specifically designed surface coil (Machnet, Leiden, NL). The imaging would start at the bifurcation of the common femoral and proceed distally. The pulse sequence used will be a black blood turbo spin echo proton density weighted sequence with 3mm slice thickness and 3mm gaps that will be subsequently interleaved. A single slice with an extensive amount of plaque will be chosen for imaging of plaque characteristics including T1- and T2-W imaging. Finally, a calf muscle perfusion study will be performed in the leg that is most symptomatic and/or has the lowest ABI in the absence of claudication symptoms. The calf will be wrapped in a flexible surface coil in a 3T scanner. Subjects will be placed supine in the MR scanner with the calf at the magnet isocenter. A thigh cuff will be inflated up to 250 mmHg for 5 min. Arterial spin labeling images of the mid-calf will be obtained immediately after release of the cuff.Regions of interest will be drawn on the relative blood flow maps corresponding to calf muscle groups to measure perfusion in ml/min/100g. Randomization: The study statistician will do a block randomization and let the pharmacy know. Patients in the treatment group will begin treatment with alirocumab or matching placebo, 150 mg subcutaneously every 2 weeks. Treatment will continue for 26 treatments or 1 year. Final Visit: This will be a repeat of the initial visit with vital signs, blood draw for lipid panel, and repeat MRI with the exact same protocol as on the initial visit.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: May 8, 2023
• Est. primary completion date: May 8, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: 35 Years to 85 Years

Eligibility

Inclusion Criteria:

• Age 35-85
• Clinical diagnosis of peripheral arterial disease
• Ankle brachial index of 0.4-0.9
• Either on statin for at least 6 months or statin intolerant. The statin used should be a high potency statin (Crestor, Lipitor) or high dose of a lower potency statin (e.g. Zocor 40-80mg, Pravachol 40-80 mg)

Exclusion Criteria:

• rest pain
• critical limb ischemia
• known or planned stent in the SFA
• known occlusion of the SFA
• planned revascularization within the next year
• inability to lie flat
• known contraindications to MRI including pacemaker, implantable cardioverter defibrillators, certain intracranial aneurysm clips, claustrophobia
• pregnancy
• known allergy to alirocumab

Related Conditions & MeSH terms

• Peripheral Arterial Disease
• Peripheral Vascular Diseases

Intervention

Drug:
• Alirocumab
150mg SQ every 2 weeks
• Matching placebo
SQ every 2 weeks

Locations

Country	Name	City	State
United States	University of Virginia Health System	Charlottesville	Virginia
United States	Northwestern University	Chicago	Illinois

Sponsors (2)

Lead Sponsor	Collaborator
University of Virginia	Northwestern University

Country where clinical trial is conducted

United States, 

References & Publications (1)

Rrapo-Kaso E, Loffler AI, Petroni GR, Meyer CH, Walker M, Kay JR, DiMaria JM, Domanchuk K, Carr JC, McDermott MM, Kramer CM. Alirocumab and plaque volume, calf muscle blood flow, and walking performance in peripheral artery disease: A randomized clinical — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in superficial femoral plaque volume (summed from both legs)	Measured by black blood MRI, expressed in cm3	1 year
Secondary	Change in calf muscle perfusion in the most symptomatic leg	Measured by arterial spin labeling MRI, expressed in ml/min/100g	1 year
Secondary	Change in plaque characteristics	% lipid in one slice from each leg	1 year
Secondary	Change in 6-minute walk test	expressed in feet	1 year
Secondary	Change in LDL cholesterol		1 year
Secondary	Change in high sensitivity c-reactive protein		1 year
Secondary	Change in fibrinogen		1 year
Secondary	Change in lipoprotein (a)		1 year