Coronary Drug Project

Coronary Drug Project
Name	Coronary Drug Project
Acronym	CDP
Start date	1965
Completion date	1975
Sponsor	National Heart Institute
Location	United States
Condition	Coronary artery disease
Intervention	Multiple pharmacologic agents
Study type	Randomized controlled trial
Enrolment	8341
Key outcome	Mortality, coronary events

Coronary Drug Project

The Coronary Drug Project was a landmark multicenter randomized clinical trial conducted in the United States to evaluate pharmacologic strategies for secondary prevention after myocardial infarction in men. The study compared multiple agents across diverse treatment arms to assess effects on mortality and coronary outcomes, influencing subsequent guidelines by organizations such as the American Heart Association and the American College of Cardiology. Its design, execution, and long-term follow-up informed later trials at institutions like Framingham Heart Study and efforts by the National Institutes of Health.

Background and objectives

The trial originated amid rising interest from the National Institutes of Health and the National Heart Institute in addressing post-myocardial infarction morbidity and mortality, with input from clinicians at Johns Hopkins Hospital, Mayo Clinic, and Massachusetts General Hospital. Investigators sought to test hypotheses generated by observational work from the Framingham Heart Study and experimental pharmacology from Merck & Co. and academic laboratories at Harvard Medical School and Stanford University. Objectives included determining whether lipid-modifying, antiarrhythmic, hormonal, and metabolic agents could reduce death and recurrent coronary thrombosis among male survivors, and whether subgroup effects varied by age, prior angina pectoris, or prior revascularization.

Study design and methods

The Coronary Drug Project employed a randomized, double-blind, placebo-controlled framework coordinated through the National Heart, Lung, and Blood Institute network of clinical centers, coordinated by methodologists from Columbia University and statisticians affiliated with University of North Carolina at Chapel Hill. Eligibility mirrored criteria used in other contemporaneous trials at Vanderbilt University and University of Minnesota: men with documented prior myocardial infarction within defined time windows. Randomization used permuted blocks managed by a central pharmacy at Walter Reed Army Medical Center, and follow-up visits paralleled protocols from trials run at Cleveland Clinic and University of California, San Francisco. Endpoints and event adjudication committees included clinicians drawn from Brigham and Women's Hospital, Duke University Hospital, and New York University Langone Medical Center.

Interventions and treatment arms

Treatment arms reflected pharmacologic diversity under development by companies and academic groups: an estrogenic derivative developed with input from researchers at Columbia University, an anticoagulant strategy reflecting work at Mayo Clinic, the fibrate family inspired by studies at University of Glasgow, and multiple lipid-lowering agents paralleling programs at Pfizer and Upjohn. The trial tested an estrogen preparation, a niacin regimen, an clofibrate-like lipid agent, an prostaglandin analog, a central nervous system agent, and multiple placebos, with dosing schemes informed by pharmacologists at University of Pennsylvania and Yale School of Medicine. Investigators from University of Michigan and University of Pittsburgh managed drug distribution, while independent monitoring committees included experts associated with Johns Hopkins University and Stanford Medical Center.

Primary outcomes and statistical analysis

Primary outcomes were all-cause mortality and coronary-specific mortality, adjudicated using criteria developed collaboratively with epidemiologists from Harvard School of Public Health and biostatisticians from University of Washington. Secondary outcomes included recurrent myocardial infarction, sudden cardiac death, and need for hospitalization, echoing endpoints used in contemporaneous trials at University of Texas Southwestern Medical Center and Wake Forest Baptist Medical Center. Statistical analysis plans invoked survival methods refined by statisticians at University of Chicago and used intent-to-treat principles championed by researchers at University of California, Los Angeles. Interim analyses were overseen by an independent data and safety monitoring board with membership drawn from Duke University School of Medicine and Emory University School of Medicine.

Results and subgroup findings

The trial enrolled approximately 8,341 men and reported differential effects across agents: one arm produced a significant reduction in nonfatal myocardial infarction but not overall mortality, while another arm—an estrogen preparation—was associated with increased mortality, prompting early discontinuation recommendations echoed in statements from American Medical Association committees. A niacin-containing regimen showed favorable effects on lipid profiles and coronary events, later corroborated by observational cohorts such as the Framingham Heart Study and interventional trials at Imperial College London and University of Oxford. Subgroup analyses suggested effect modification by age strata and history of angina pectoris, similar to heterogeneity seen in trials run at Karolinska Institute and McMaster University.

Safety, adverse effects, and discontinuations

Adverse effect monitoring revealed significant harms in specific arms, including increased thromboembolic events and hormonal side effects that paralleled safety signals later described in studies from Royal Brompton Hospital and pharmacovigilance reports from Food and Drug Administration. Discontinuations for adverse events were frequent in the estrogen arm and in certain lipid-agent arms, with safety oversight coordinated with expert panels from National Academy of Medicine and legal review by counsel associated with U.S. Department of Health and Human Services. The pattern of adverse events influenced regulatory actions and prescribing guidance disseminated through the American College of Physicians and clinical bulletins from Beth Israel Deaconess Medical Center.

Legacy, impact, and subsequent research

The Coronary Drug Project reshaped cardiovascular therapeutics, informing guideline development by the American Heart Association, influencing lipid research at centers including Johns Hopkins University School of Medicine and University of California, San Diego, and prompting mechanistic studies at Massachusetts Institute of Technology and Salk Institute laboratories. Its long-term follow-up methods were adopted by trials such as the Scandinavian Simvastatin Survival Study and the Heart Protection Study, and its findings stimulated meta-analyses by consortia at Cochrane Collaboration and policy evaluations by the Institute of Medicine. Subsequent trials of niacin and lipid-modifying strategies at University College London and Vanderbilt University Medical Center built on its results, while its safety controversies informed modern data and safety monitoring practices at World Health Organization–endorsed networks.

Category:Clinical trials