"In the first prospectively designed study of cognitive function with a PCSK9 inhibitor using validated instruments, we showed that there were no significant differences between patients taking evolocumab and those on placebo," said Robert P. Giugliano, M.D., S.M., Brigham and Women's Hospital, Boston and lead study investigator. "These findings are reassuring for both physicians and patients because they show that LDL cholesterol levels can be lowered with evolocumab to levels well below current treatment targets, with no negative effects on memory or other cognitive domains."
The effect of Repatha on executive function (primary endpoint) was non-inferior to placebo, and there was no statistical difference between Repatha and placebo on the other cognitive domains tested: working memory, memory function and psychomotor speed (secondary endpoints).
"Historically, the clinical cardiology community has had concerns that low LDL-C levels may impact cognitive function," said Sean E. Harper, M.D., executive vice president of Research and Development at Amgen. "Across our comprehensive clinical trial program, thousands of patients have been treated with Repatha, which has demonstrated a consistent safety profile, even at very low LDL cholesterol levels. These findings add to the body of evidence supporting the safety of LDL-lowering with Repatha in patients with established cardiovascular disease who need more than statin therapy alone."
In the primary cohort of 1,204 patients, followed for a median of 19 months, the change from baseline raw score of spatial working memory strategy index of executive function was similar in the Repatha and placebo groups (mean baseline score 17.8; mean change from baseline -0.21 versus -0.29, respectively). The primary endpoint was below the pre-specified margin, demonstrating non-inferiority. The primary endpoint was assessed by the Cambridge Neuropsychological Test Automated Battery (CANTAB) Spatial Working Memory strategy index of executive function. CANTAB is an established, language- and culture-independent, computerized, tablet-based cognitive assessment tool that uses touchscreen neuropsychological tests of cognition specifically designed to assess central nervous system disorders and cognitive function across a range of domains, including episodic and working memory, executive function, psychomotor speed and attention.
Secondary endpoint results in the three cognitive domains of working memory, memory function and psychomotor speed were consistent with the primary endpoint result, and patients treated with Repatha experienced changes from baseline similar to placebo in all three cognitive domains tested. Changes from baseline in the global composite score were also similar between treatment arms.
In an exploratory analysis, results were consistent regardless of achieved low-density lipoprotein cholesterol (LDL-C) levels and did not show an association between LDL-C level and adverse cognitive outcomes, including in the 661 patients with the lowest-achieved LDL-C level (<25 mg/dL).
In the EBBINGHAUS study, neurocognitive adverse event rates were similar between treatment arms (1.9 percent Repatha; 1.3 percent placebo). The adverse events identified in EBBINGHAUS were consistent with the adverse events identified in the 27,564-patient Repatha cardiovascular outcomes study FOURIER.
The results were initially presented at a Late-Breaking Clinical Trial Session at the American College of Cardiology 66th Annual Scientific Session (ACC.17) in March 2017.
Repatha Cognitive Function (EBBINGHAUS) Study Design
EBBINGHAUS (Evaluating PCSK9 Binding antiBody Influence oN coGnitive HeAlth in high cardiovascUlar risk Subjects) is a double-blind, placebo-controlled, randomized non-inferiority trial involving 1,974 patients with clinically evident atherosclerotic cardiovascular disease enrolled in the Repatha cardiovascular outcomes study (FOURIER). The primary non-inferiority assessment of the primary endpoint of spatial working memory strategy index of executive function (assessing executive function, or high-level thinking and decision making) was performed on the primary cohort of 1,204 patients who enrolled on or before the first dose of investigational product and had at least one post-baseline CANTAB assessment. The full cohort (1,974 patients) included all randomized patients. The primary endpoint was assessed by comparing the 95 percent confidence interval (CI) with the pre-specified non-inferiority margin for the treatment difference between Repatha and placebo. Secondary endpoints were the CANTAB Spatial Working Memory between-errors score (assessing working memory, or the ability to hold material in mind while that material is being actively processed); the CANTAB Paired Associates Learning Total Errors Adjusted (assessing memory function, or the ability to store and retrieve information by associating an event with a time and place); and the CANTAB Reaction Time Five-Choice Median Reaction Time (assessing psychomotor speed, which is responsible for detecting and responding to a stimulus). For all three secondary endpoints, the 95 percent CI for the estimated treatment difference between Repatha and placebo spanned equivalence.
Primary and secondary endpoints were assessed using a tablet-based tool at baseline, week 24, yearly and at study end. The primary analysis compared the mean change from baseline in patients who had a baseline cognitive assessment on or prior to the first day of study drug.
Repatha Cardiovascular Outcomes (FOURIER) Study Design
The 27,564-patient Repatha cardiovascular outcomes study, FOURIER (Further Cardiovascular OUtcomes Research with PCSK9 Inhibition in Subjects with Elevated Risk), was a multinational, Phase 3, randomized, double-blind, placebo-controlled trial, designed to evaluate whether treatment with Repatha in combination with statin therapy compared to placebo plus statin therapy reduces cardiovascular events. The hard major adverse cardiovascular event (MACE) composite endpoint was time to cardiovascular death, myocardial infarction or stroke (key secondary endpoint). The extended MACE composite endpoint was the time to cardiovascular death, myocardial infarction, stroke, hospitalization for unstable angina, or coronary revascularization (primary endpoint).
Eligible patients with high cholesterol (LDL-C =70 mg/dL or non-high-density lipoprotein cholesterol [non-HDL-C] =100 mg/dL) and clinically evident atherosclerotic cardiovascular disease at more than 1,300 study locations around the world were randomized to receive Repatha subcutaneous 140 mg every two weeks or 420 mg monthly plus optimized statin dose; or placebo subcutaneous every two weeks or monthly plus optimized statin dose. Optimized statin therapy was defined as at least atorvastatin 20 mg or equivalent daily with a recommendation for at least atorvastatin 40 mg or equivalent daily where approved. The study was event driven and continued until at least 1,630 patients experienced a key secondary endpoint.
About Repatha® (evolocumab)
Repatha® (evolocumab) is a human monoclonal antibody that inhibits proprotein convertase subtilisin/kexin type 9 (PCSK9). Repatha binds to PCSK9 and inhibits circulating PCSK9 from binding to the low-density lipoprotein (LDL) receptor (LDLR), preventing PCSK9-mediated LDLR degradation and permitting LDLR to recycle back to the liver cell surface. By inhibiting the binding of PCSK9 to LDLR, Repatha increases the number of LDLRs available to clear LDL from the blood, thereby lowering LDL-C levels.(1)
Repatha is approved in more than 50 countries, including the U.S., Japan, Canada and in all 28 countries that are members of the European Union. Applications in other countries are pending.
About Amgen Cardiovascular
Building on more than three decades of experience in developing biotechnology medicines for patients with serious illnesses, Amgen is dedicated to addressing important scientific questions to advance care and improve the lives of patients with cardiovascular disease, the leading cause of morbidity and mortality worldwide.(2) Amgen's research into cardiovascular disease, and potential treatment options, is part of a growing competency at Amgen that utilizes human genetics to identify and validate certain drug targets. Through its own research and development efforts, as well as partnerships, Amgen is building a robust cardiovascular portfolio consisting of several approved and investigational molecules in an effort to address a number of today's important unmet patient needs, such as high cholesterol and heart failure.
Amgen is committed to unlocking the potential of biology for patients suffering from serious illnesses by discovering, developing, manufacturing and delivering innovative human therapeutics. This approach begins by using tools like advanced human genetics to unravel the complexities of disease and understand the fundamentals of human biology.
Amgen focuses on areas of high unmet medical need and leverages its expertise to strive for solutions that improve health outcomes and dramatically improve people's lives. A biotechnology pioneer since 1980, Amgen has grown to be one of the world's leading independent biotechnology companies, has reached millions of patients around the world and is developing a pipeline of medicines with breakaway potential.
1. Repatha® U.S. Prescribing Information. Amgen.
2. World Health Organization. Cardiovascular diseases (CVDs) fact sheet. http://www.who.int/mediacentre/factsheets/fs317/en/. Accessed March 2017.