Understanding Clinical Research

Device and drug testing commences with laboratory research that can encompass years of experiments on animals and on human cells. If the primary laboratory research turns out to be successful, then the researchers send the information to Food and Drug Administration (FDA) for consent for the continuation of the research and testing on humans.

Once the drug and device has been approved, human testing of the experimental drug and the devices can commence and typically takes place in four different stages. Every phase is considered as separate trials and after the completion of the specific phases, the investigators have to turn in their data from FDA prior to continuing to the next phase.

Procedure of human clinical trails

Phase I studies

The phase 1 studies evaluate the safety of the drug or the device. This primary phase of testing can take up to multiple months to finish, normally encompasses a small number of healthy volunteers mainly from 20 to 100 people. The people are paid for participating in the phase. The whole study is designed to determine the impact of the device or the drug on humans including how it is taken in, metabolised and then excreted. This phase of study also investigates side effects, if any, which might occur when the number of doses is increased. More than 65% of the experimental drugs have to undergo this phase of testing.

Phase II studies

The second phase of study tests the efficacy of the device or the drug. This second phase of study can last up to several months or up to two years and includes multiple patients. Most of the second phase of studies are unsystematic trials where a group of patients is divided into two, first group of the patients get the experimental drug while the second half of the whole group gets a standard treatment or a placebo. Often this phase is blinded which signifies that neither the researcher nor the patient is aware of which group received the experimental drug. This permits the investigators to offer pharmaceutical company and the FDA comparative details about the relative safety and effectiveness of the fairly new drug. One third of the experimental drugs successfully finish both the initial phases of the studies.

Phase III studies

This phase of study includes unsystematic as well as blind testing in multiple hundreds to thousands of patients. This broad scale testing that can last upto multiple years offer the FDA and the pharmaceutical company a detailed comprehension of the effectiveness of the drug or the device, the perks and the range possible adverse reaction of the drug or device. More than 70 to 90% of the drugs that make it to this phase are able to complete the requirement of the testing of this phase. Once the third phase has been completed, the pharmaceutical company can make a request to the FDA to approve the marketing of the drug or device.

Phase IV studies

The study of the fourth stage is known as the post-marketing surveillance trails that are conducted after the device or the drug has been approved for sale to the consumers. The pharmaceutical companies have multiple objectives at this stage, such as:

  • Compare the new drug with the drugs that already exist in the market.
  • Monitor the long term effectiveness of the drug as well as its impact on the life of the patient.
  • Determine the cost effectiveness of the drug therapy with the traditional as well as new therapies.

The fourth phase of studies can result in the device or the drug being taken off from the market or restrictions being placed on its use depending upon the outcome that it can produce in the market.