Clinical trial

Clinical trial
NIAID · CC BY 2.0 · source
Name	Clinical trial
Purpose	Evaluation of interventions in human participants
Start date	Ancient to present
Location	Worldwide

Clinical trial is a structured research study that evaluates medical, surgical, behavioral, or diagnostic interventions in human participants. Clinical trials are conducted by academic institutions, pharmaceutical companies, contract research organizations, and public health agencies to generate evidence on efficacy, safety, dosing, and comparative effectiveness. Trials inform policy, regulatory decisions, clinical guidelines, and the development of therapeutics and devices.

Overview

Clinical trials typically proceed from initial hypothesis testing to large-scale comparative studies and are undertaken at centers such as Mayo Clinic, Johns Hopkins Hospital, Massachusetts General Hospital, University of Oxford, Karolinska Institutet, Harvard Medical School, Stanford University School of Medicine, University of Cambridge, Imperial College London, National Institutes of Health, Food and Drug Administration, European Medicines Agency, World Health Organization, Centers for Disease Control and Prevention, Bill & Melinda Gates Foundation, Wellcome Trust, GlaxoSmithKline, Pfizer, Roche, Novartis, AstraZeneca, Merck & Co., Johnson & Johnson, Eli Lilly and Company, Bristol-Myers Squibb, Sanofi, Takeda Pharmaceutical Company, Bayer AG, AbbVie, Gilead Sciences, Regeneron Pharmaceuticals, Moderna, Inc., BioNTech, Oxford–AstraZeneca vaccine collaborations. Multicenter trials may involve networks like Coordinating Centers for Clinical Trials and consortia such as ClinicalTrials.gov-registered studies and initiatives linked to World Health Assembly priorities. Funding, sponsorship, and intellectual property arrangements vary across entities such as National Cancer Institute, European Commission, Wellcome Trust, and philanthropic organizations like Chan Zuckerberg Initiative.

Design and Phases

Trial designs include randomized controlled trials, adaptive trials, crossover trials, noninferiority trials, pragmatic trials, and platform trials used in responses to emergent threats like those coordinated during the Ebola virus epidemic in West Africa and the COVID-19 pandemic. Early-phase studies (Phase I) often take place at specialist units such as Phase I Clinical Trials Units affiliated with institutions like University of Pennsylvania or King's College London; Phase II and III trials may be conducted by networks including National Institutes of Health Clinical Center and multinational sponsors participating in consortia such as Translational Research initiatives. Phase IV postmarketing surveillance uses registries and programs run by agencies like the Food and Drug Administration and the European Medicines Agency to monitor long-term outcomes. Trial design considerations reference regulatory frameworks such as the Declaration of Helsinki, the Nuremberg Code, the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use, and statutes like the Food, Drug, and Cosmetic Act.

Ethical and Regulatory Considerations

Ethics oversight is provided by institutional review boards and ethics committees at institutions such as Harvard Medical School and regulatory authorities including the Food and Drug Administration and the European Medicines Agency. Consent processes draw on guidance from documents like the Declaration of Helsinki and governance from bodies such as the World Health Organization and national ministries of health. Conflicts of interest, data transparency, and access are influenced by policies from organizations like National Institutes of Health, Wellcome Trust, and journals including The Lancet, The New England Journal of Medicine, JAMA, and BMJ. Legal frameworks such as the Health Insurance Portability and Accountability Act of 1996 affect data protection and participant privacy in trials conducted at centers like Mayo Clinic and Cleveland Clinic.

Methodology and Endpoints

Methodological elements incorporate randomization procedures developed in contexts such as Randomized controlled trial history and allocation concealment methods used by research groups at University of Oxford and University of Cambridge. Common endpoints include clinical outcomes endorsed in guidelines by organizations like the World Health Organization, surrogate markers validated in studies from National Cancer Institute programs, and patient-reported outcomes promoted by initiatives such as the Patient-Centered Outcomes Research Institute. Biomarkers and diagnostic assays are often developed in translational labs at institutions like Cold Spring Harbor Laboratory and Broad Institute.

Safety Monitoring and Adverse Events

Safety oversight is managed via data monitoring committees and pharmacovigilance systems coordinated with agencies such as the Food and Drug Administration and the European Medicines Agency. Serious adverse event reporting procedures follow standards set by regulatory programs like the Clinical Data Interchange Standards Consortium and trials sponsored by companies such as Pfizer and GlaxoSmithKline routinely engage independent data safety monitoring boards. Postmarket surveillance integrates spontaneous reporting systems such as Vaccine Adverse Event Reporting System and pharmacoepidemiology studies conducted by organizations like the Centers for Disease Control and Prevention.

Statistical Analysis and Reporting

Statistical planning relies on methods popularized by statisticians associated with institutions like University of Oxford and University of Cambridge, employing intention-to-treat analysis, per-protocol analysis, survival analysis, and interim analyses in trials run by groups such as the National Cancer Institute cooperative groups. Reporting standards follow guidelines from entities like the Consolidated Standards of Reporting Trials (CONSORT) group and journal policies of The New England Journal of Medicine, The Lancet, JAMA, and BMJ. Data sharing initiatives involve repositories and platforms supported by National Institutes of Health, Wellcome Trust, and international consortia such as the Global Alliance for Genomics and Health.

Historical Development and Impact

The evolution of modern trials draws lines from early controlled experiments associated with figures and events like Edward Jenner, James Lind, the rise of randomized methods in the 20th century influenced by researchers at London School of Hygiene & Tropical Medicine and the Medical Research Council (United Kingdom), and landmark regulatory milestones such as the passage of the Food, Drug, and Cosmetic Act and establishment of the European Medicines Agency. High-profile trials and vaccine development efforts during the HIV/AIDS epidemic, the Ebola virus epidemic in West Africa, and the COVID-19 pandemic accelerated innovations in adaptive platform trials and global collaboration among institutions including World Health Organization, Centers for Disease Control and Prevention, National Institutes of Health, Oxford University, Moderna, Inc., BioNTech, and Pfizer. The cumulative impact of trials has reshaped clinical practice, medical education at schools like Harvard Medical School and Johns Hopkins School of Medicine, and health policy deliberations in forums such as the World Health Assembly.

Category:Clinical research