What are Clinical Trials?
Clinical trials are organized to collect data for checking the safety and efficiency of new drugs and medical devices. There are four major Phases of clinical trials. For a drug or device to be sold outside, first the drug should pass all the clinical trial phases. The clinical research process takes years for its completion. The experiments are done on animal and human cells to rule out the efficacy. Once the initial laboratory research is completed then the drug is sent to FDA for approval. The FDA starts the research again by testing it on humans.
The testing of drugs and devices on humans is the basis of a clinical trial. Each phase of the clinical trial is carried out in series one by one. After completion of one phase, the reports are sent to FDA for approval. A yes from FDA is required to start the next phase. The clinical trial phases are discussed below:
Phase I of a clinical trial:
This phase assesses the safety of a drug. The test is done on a small number of volunteers (20 to 70 peoples). It examines how the drug is absorbed, metabolized, and excreted in the human body. The side effects of overdose are also assessed. Almost 70%of the drugs pass this phase easily.
Phase II of a clinical trial:
This phase assesses the efficacy of the drugs. This phase can last from months to 2 years. The test is done on hundreds of people. Phase 2 consists of majorly randomized trials where 1 group is given the experimental drug and the other is the control group receiving the standard treatment or placebo. These are blinded studies so as to allow the investigators to provide reliable information on safety and efficiency of drugs to FDA and the pharmaceutical company. Only one-third of the experimented drug pass this trial.
Phase III of a clinical trial:
This phase assesses the effectiveness of a drug to treat or cure the specific disease. Phase III of a clinical trial is the longest phase out of all the phases. The test is done for 300 to 3000 participants. The participants are the ones who are living with the targeted condition that the drug is made for. One other requisite of participants is a similar demographic trait. Participants with similar traits can only participate and they are tested for 3 to 5years.
The purpose is to intensive study on the safety, efficacy, and dose of drugs. Side effects and benefits of minimum dosage and over dosage are also examined in this step. Only 20% of the drugs pass this phase of clinical trials.
Phase IV of a clinical trial:
This phase is also called Post Marketing Surveillance Trials. This phase is carried out when the device has been approved for sale in outside market. This phase checks side effects and safety of drugs intensively; the long-term risks and benefits; and how the drug works when used widely. This phase can even result in a drug being taken out from the market or restriction of use.