Clinical research
Encyclopedia
Clinical research is a branch of medical science that determines the safety and effectiveness of medications, devices
Medical device
A medical device is a product which is used for medical purposes in patients, in diagnosis, therapy or surgery . Whereas medicinal products achieve their principal action by pharmacological, metabolic or immunological means. Medical devices act by other means like physical, mechanical, thermal,...

, diagnostic products and treatment regimens intended for human use. These may be used for prevention, treatment, diagnosis or for relieving symptoms of a disease.

Overview

The term clinical research refers to the entire bibliography of a drug/device/biologic, in fact any test article from its inception in the lab to its introduction to the consumer market and beyond. Once the promising candidate or the molecule is identified in the lab, it is subjected to pre-clinical studies or animal studies where different aspects of the test article (including its safety toxicity if applicable and efficacy, if possible at this early stage) are studied.

In the United States, when a test article is unapproved or not yet cleared by the FDA, or when an approved or cleared test article is used in a way that may significantly increases the risks (or decreases the acceptability of the risks), the data obtained from the pre-clinical studies or other supporting evidence, case studies of off label use, etc. are submitted in support of an Investigational New Drug
Investigational New Drug
The United States Food and Drug Administration's Investigational New Drug program is the means by which a pharmaceutical company obtains permission to ship an experimental drug across state lines before a marketing application for the drug has been approved...

 (IND) application to the Food and Drug Administration (FDA) for review prior to conducting studies that involve even one human and a test article if the results are intended to be submitted to or held for inspection by the FDA at any time in the future (in the case of an already approved test article, if intended to submit or hold for inspection by the FDA in support of a change in labeling or advertising). Where devices are concerned the submission to the FDA would be for an Investigational Device Exemption
Investigational Device Exemption
An Investigational Device Exemption allows the investigational device to be used in a clinical study in order to collect safety and effectiveness data required to support a Premarket Approval application or a...

 (IDE) application if the device is a significant risk device or is not in some way exempt from prior submission to the FDA. In addition clinical research may require Institutional Review Board
Institutional review board
An institutional review board , also known as an independent ethics committee or ethical review board , is a committee that has been formally designated to approve, monitor, and review biomedical and behavioral research involving humans with the aim to protect the rights and welfare of the...

 (IRB) or Research Ethics Board (REB) and possibly Other institutional Committee reviews, Privacy Board, Conflict of Interest Committee, Radiation Safety Committee, Radioactive Drug Research Committee, etc.]] approval whether or not the research requires prior submission to the FDA. Clinical research review criteria will depend on which Federal regulations the research is subject to (e.g., [(Department of Health and Human Services (DHHS) if Federally funded, FDA as already discussed) and will depend on which regulations the institutions subscribe to, in addition to any more stringent criteria added by the institution possibly in response to state or local laws/policies or accreditation entity recommendations. This additional layer of review (IRB/REB in particular) is critical to the protection of human subjects especially when you consider that often research subject to the FDA regulation for prior submission is allowed to proceed, by those same FDA regulations, 30 days after submission to the FDA unless specifically notified by the FDA not to initiate the study.

In the European Union, the European Medicines Agency
European Medicines Agency
The European Medicines Agency is a European agency for the evaluation of medicinal products. From 1995 to 2004, the European Medicines Agency was known as European Agency for the Evaluation of Medicinal Products.Roughly parallel to the U.S...

 (EMA) acts in a similar fashion for studies conducted in their region. These human studies are conducted in four phases in research subjects that give consent to participate in the clinical trials.

Phase 1 trials

This phase is also called as first in humans. Phase 1 trials usually deal with investigating the studied drug in a minor number of research subjects (e.g. 10) who are healthy volunteers. This phase is mainly targeted at identifying the safety, tolerability, and the general mechanism of the action of the drug in humans.

These studies are usually conducted in tightly controlled clinics called CPUs (Central Pharmacological Units), where participants receive 24-hour medical attention and oversight. In some diseases in which the therapy under study is known to be too toxic for healthy subjects (some cancer medications, for instance), phase 1 trials are performed in patients with diseases to test these parameters.

Phase 2 trials

The goal of phase 2 trials is to grasp additional understanding of the studied drug's safety and efficacy. It also determines the appropriate dose to be administered to deliver the desired treatment effect while minimizing the safety risk of future research subjects. This usually requires more than 100 patients to demonstrate relevant results, although the actual number of subjects varies widely based on the disease under study. Thus, multiple clinics are utilized to recruit subjects with the disease under study to sufficiently enroll the study(ies) in a reasonable period of time.

Phase 3 trials

This is also called pre marketing. Multiple phase 2 studies are often required to define the appropriate patient population to study during phase 3. Once the drug is deemed a potentially safe and effective candidate in Phase 2, it is then studied in Phase 3 trials. This phase often exposes more than 1000 research subjects with the disease, and is usually performed at many clinics (sometimes well over 100) to enroll the trial (or trials). There is a focus on the effectiveness of the study drug in a variety of demographic and socioeconomic subjects with variants of the disease under study. A comparison is usually made with standard drugs available on the market. It is imperative that the drug is shown to be effective and safe in this phase.

When phase 3 trials are completed (as well as the data demonstrating safety and efficacy of the study drug), a New Drug Application
New drug application
The New Drug Application is the vehicle in the United States through which drug sponsors formally propose that the Food and Drug Administration approve a new pharmaceutical for sale and marketing...

 (NDA) containing all manufacturing, pre-clinical, and clinical data is filed with the FDA for review. If deemed safe and effective, the FDA grants approval of the NDA, which then allows the company to market the product. This approval usually comes with strict requirements for the company to conduct additional studies to keep the NDA active (usually involving pediatric trials and additional safety trials).

Phase 4 trials

This phase is also called as post-marketing surveillance phase.In phase 4, the aim is to further characterize the safety of the drug through the identification of unknown adverse reactions and to potentially research new therapeutic indications. Companies often use this phase to gain exposure to different physicians and clinics, which aids in the marketing of their product. The entire process of a drug from lab to market may take approximately 12 to 18 years (but not always), costing billions of dollars.

Further trials

Clinical research continues throughout the lifetime of the test article to include post marketing surveillance
Postmarketing surveillance
Postmarketing surveillance is the practice of monitoring the safety of a pharmaceutical drug or device after it has been released on the market and is an important part of the science of pharmacovigilance...

 where a periodic 'progress report' is submitted to the regulatory authorities once every 2 years after the test article is released into the market, and such as pharmacovigilance
Pharmacovigilance
Pharmacovigilance is the pharmacological science relating to the detection, assessment, understanding and prevention of adverse effects, particularly long term and short term side effects of medicines...

where the safety of marketed drugs, biologics or medical devices are monitored.

The focus of clinical research is wide enough to include important items such as data management, medical writing, regulatory consultation, and biostatistics.

The clinical trials are regulated by country specific Health Regulatory Agencies such as the Food and Drug Administration (FDA) in the U.S. and the European Medicines Agency (EMEA) in the European Union.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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