Before new medications or medical technology and devices can be approved for use, they must undergo extensive clinical trials. Clinical trials establish the safety and efficacy of drugs, treatments and devices. They typically last for years and go through four phases. People who participate in clinical trials are volunteers and patients who must be informed about all aspects of the medication or procedure. Ethical as well as scientific considerations are used to regulate clinical trials.
Clinical trials: the phases
The four stages of clinical study begin with experiments or observations on small groups of human subjects for a pilot study. These may involve biomedical or behavioral research on new treatments, vaccines, drugs, dietary regimes, supplements and medical devices. Phase 1 clinical trials begin with a small pilot study involving 20-80 people.
As the clinical trials progress, the number of participants increases progressively for large scale comparative studies. Clinical trials can be conducted at one or multiple centers and also in a single country or in many different countries simultaneously. They are typically sponsored and funded by government agencies or pharmaceutical, biotech or medical device companies. Clinical drug development must follow strict scientific and ethical guidelines.
The importance of informed consent
Ethical considerations are as important as scientific ones in medical research. All human subjects must be fully informed about the nature of the trials, the possible results, and potential benefits and harms. For subjects who are underage or who are unable to consent for some other reason, their legal guardians or representatives must provide consent.
Typically research proposals must be approved by an Institutional Review Board (IRB), which ensure that the proposed research will not harm participants in any way. Even in scientific research, it is nearly impossible to foresee all outcomes. However ethical research guidelines provide standards to which researchers must conform.
Clinical trials maintain high standards
Medical research studies depend on clinical trials to develop new drugs and treatments. The process is long and demanding, and the approval process is very stringent. By 2005, clinical trials typically lasted 780 days, up from 460 days in 1999. This allows researchers to test the efficacy as well as safety of the new drugs or treatment.
After the completion of clinical trials, the sponsors submit a New Drug Application (NDA), which must be approved before the drug can be marketed. Each year, out of the 5,000-10,000 drugs that enter RandD, only 250 make it to the next stage, which is pre-clinical trial testing. The next cut is clinical trials, with one five out of the original thousands making it this far. In the end, only one will win FDA approval.
Clinical trials help move forward medical knowledge and treatments. Many people who participate in clinical trials see this as a kind of public service, like giving blood, and just as essential to the healthcare system.