Clinical trials are a part of clinical research. They look at new ways to prevent, detect or treat new diseases. They are designed to answer specific questions about biomedical or behavioral interventions. Clinical trials offer hope for many people and an opportunity to help researchers find better treatments for others in the future.
Goal of clinical trials: The goal of clinical trials is to generate data on safety (whether the drug is safe enough) & efficacy (whether the drug works well enough) of the tested drug (originated by sponsors) in humans.
- The sponsor, who has developed new drug, could be a governmental organization or a pharmaceutical, biotechnology or medical device company.
- Clinical trials are conducted only after the sponsor has received health authority/ethics committee approval in the country where the trial is going to be conducted. These committees are responsible for testing the risk/benefit ratio of the trial. Their approval does not mean that the therapy is ‘safe’ or effective, only that the trial may be conducted.
- Depending on the product type and development stage, investigators (doctors) initially enroll volunteers or patients into small pilot studies and then, conduct progressively larger scale comparative studies. Volunteers for the clinical trials are not paid for participating. They participate in clinical trials for a variety of reasons such as,
- Healthy volunteers participate to help others and to contribute to moving science forward.
- Patients participate either to help others or to possibly receive the newest treatment and to have the additional care and attention from the clinical trial staff.
- Clinical trials can vary in size & cost and they can involve a single research center or multiple centers, in one country or in multiple countries.
- Clinical trials are conducted according to a plan known as a protocol. The protocol is carefully designed to safeguard the participant’s health and answer specific research questions. A protocol describes the following:
- Who is eligible to participate in the trial
- Details about tests, procedures, medications and dosages
- The length of the study and what information will be gathered
- Clinical trials involving new drugs are commonly classified into four phases.
- Phase I trial: Researchers test an experimental drug or treatment in a small group of volunteers (20–80) for the first time. The purpose is to evaluate its safety and identify side effects.
- Phase II trials: The experimental drug or treatment is administered to a larger group of patients (100–300) to determine its effectiveness and to further evaluate its safety.
- Phase III trials: The experimental drug or treatment is administered to large groups of patients (1,000–3,000) to confirm its effectiveness, monitor side effects, compare it with standard or equivalent treatments and collect information that will allow the experimental drug or treatment to be used safely.
- Phase IV trials: After the drug is approved by FDA and made available to the public, researchers track its safety, seeking more information about a drug or treatment’s risks, benefits, and optimal use.
While starting a clinical trial, investigator recruits patients with the predetermined characteristics, administer the treatment and collect data on the patient’s health for a defined time period. Researchers send the data to the trial sponsor, who then analyzes the pooled data using statistical tests.