Clincal trials are performed to define new treatments or identify potential medicines for benefit of patients. This article includes various types of clinical trials and different phases in its study.
1.0 Introduction
Clinical study performs research involving human volunteers or participants with the aim to provide medical knowledge. Clinical study is further divided into clinical studies and observational studies.
Clinical trials are a subset of clinical research and are performed to find various ways to detect, treat and prevent disease or improve quality of life for patients with chronic condition. In accordance with specific interventions, in drugs, medicinal products or devices, given by protocol or research plan the clinical trials are performed. They compare new medical approach to an already available standard approach. As the new product being tested is completely unknown therefore safety and efficacy are measured basing on the outcomes of participants.
1.1 Origin
Clinical trials originate from laboratory where researchers initially test new procedures or therapies are done either in lab or animal studies. In these trials information on experimental treatment, risks and efficacy are known.
1.2 Protocol
The plan according to which the clinical research is carried out is called protocol. It is defined in a way to safeguard the participants’ health and support for research. It describes the eligibility criteria of the participant to take part in trial, detailed information on procedures, dosages, tests and medications.
This study is led by Principal Investigator who is a doctor. The research team monitors the patients’ health regularly to determine safety and efficacy.
1.3 Location
Clinical trials take place at various locations like universities, hospitals, community clinics or doctor’s office. Depending on who conducts the study the location is selected.
1.4 Timeframe
Depending on what is being studied in the clinical trial the length of the study varies.
1.5 Sponsor
Clinical trials are funded by federal agencies like National Institutes of Health, U.S. Department of Veterans Affairs, U.S. Department of Defense, Pharmaceutical companies, voluntary groups and academic medical centers. In addition health care providers or individual sponsors or other organizations can also sponsor.
1.6 Informed Consent
It is the process where key facts about the clinical trial are provided to the participants before participating in the study. The details like duration, purpose, risks and potential benefits of the study are further explained by the research team to the participants including translating the content. This consent is to be signed by the participant and they can withdraw at any time making them ineligible for the study.
2.1 Types of clinical trials
Depending on their functionality different clinical trials can be given.
i) Natural history studies: these studies provide information on disease and health progression.
ii) Prevention trials: they help in finding out better ways in term of medicines, lifestyle changes or vaccines to prevent the disease or prevent its reoccurrence.
iii) Screening trials: they help in detecting the certain health conditions or diseases.
iv) Diagnostic trials: they determine best procedures to diagnose disease.
v) Treatment trials: they test new treatments or combinations or approaches to radiation therapy or surgery.
vi) Quality of life trials: they measure or explore ways to improve quality of life and comfort to people with chronic conditions.
2.2 Phases of Clinical trials
They are done in four phases with a different purpose in each phase.
Phase I trials
An experimental drug or any treatment is tested in a small group of 20 – 80 people. Safety is evaluated and side effects are identified in this phase.
Phase II trials
An experimental drug or treatment is tested in a larger group of 100-300 people. Safety is evaluated and efficacy is determined.
Phase III trials
An experimental drug or treatment is tested in larger group of 1,000-3,000 people to evaluate its safety, efficacy and side effects are monitored. Here the responses are compared with the standard or equivalent treatments.
Phase IV trials
After FDA approves the drug it is made available in the market where it is tracked for its benefits, safety, risks, and use by the researchers.
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