What Are The Phases Involved In A Clinical Trial?

Clinical trials are conducted for collecting data related to safety as well as the efficacy of new drug along with device development. There are various steps as well as stages of approval in such a trial. A drug or a device cannot be released in the market without passing these essential phases.

Before conducting any clinical trials in people, doctors must prove that their explanation on how the treatment works is right. This explanation is called the research hypothesis. The research community calls this stage, which takes place in a laboratory, preclinical research. It often takes years for doctors to turn information from this stage into a new treatment…Source: cancer.net

The Clinical trial phases

• Phase 1

This phase examines the drug or device’s safety. This first stage of the entire process can be lengthy and take a considerable amount of months for completion. It usually involves some healthy volunteers who are paid for participating in this phase. This phase is done for determining the effect of the drug on the volunteer including its absorption, metabolization and finally excretion. The phase also studies the possible side effects due to increase in the level of dosage.

• Phase 2

This stage examines the efficacy of the drug or the device. This second stage can last from some months to more than one year, involving several patients. Most of this phase 2 involves randomized trials where some patients receive the experimental drug while the remaining people receive a standard treatment. Both the researchers as well as the patients do not know who has got the drugs. This allows them to provide sufficient information about its safety and efficiency to the heads.

• Phase 3

This stage involves a large scale testing which lasts for several years and provides the FDA as well as the pharmaceutical company with more knowledge about the drug’s effectiveness, benefits, and possible side effects. After this stage is finished, it can be brought into the market upon request.

• Phase 4

This phase is known by the name of post-marketing surveillance trials and is conducted after the drug or service is approved for customer sale. A pharmaceutical company’s main objectives are comparing the drug with other drugs in the market, monitoring the drug’s long-term effectiveness as well as its impact on the patient’s life.