What types of trials are there?
Comparative studies and Open Label studies are the two groups of clinical trials. The following will detail the differences between the two types of trials, as well as explain what each type of trial involves. In addition, below you will learn more about the four phases of clinical trials – Phase I, II, III and IV – that new drugs and treatments go through before entering the market.
Comparative Clinical Research Trials
Comparative, also known as controlled, clinical trials involve one group of patients who receive the new drug and a control group who receives a placebo or gold standard treatment. A placebo is an injection, infusion or pill that seems identical to the new treatment, but is actually inactive. Comparative studies are typically conducted as double-blind trials, where neither the physician nor the patient knows which group is receiving the new drug. Double-blind trials help to eliminate any biased results.
Open Label Clinical Research Trials
Open Label clinical trials do not attempt to disguise the new drug or treatment, meaning that no standard treatment or placebo is utilized. This leans towards bias, as both the patient and the physician are aware of which groups are receiving what type of treatment.
The Four Phases of Clinical Research Trials
The four phases of clinical trials are Phase I, Phase II, Phase III and Phase IV. These phases are all separate and individual clinical studies. The entire process from Phase I to Phase IV can take anywhere from eight to 10 years to complete. In more detail, the four clinical trial phases are:
Phase I Clinical Trials: The first phase involves testing new drugs or treatments for safety, efficacy and dosage on healthy volunteers on an in-patient basis.
Phase II Clinical Trials: Read more about Phase II studies that further evaluate safety, efficacy and toxicity of new drugs and treatments on patients afflicted with the targeted condition.
Phase III Clinical Trials: Click here to find out more about Phase III trials, which definitively assess the efficacy of new drugs on large groups of patients in multicenter trials.
Phase IV Clinical Trials: Educate yourself about the last stage of clinical trials, where post-marketing testing is done to further evaluate the benefits and risks of the new drug or treatment.
The Most Common Questions:
- What is a Clinical Research Study?
- Why Participate in a Clinical Research Study?
- What’s the Difference Between Clinical Trials and Treatments?
- How Do You Test Investigational Drugs?
FAQ’s on Clinical Trials:
Understand Your Rights:
- Your Rights as a Patient
- Rights to Privacy
- Informed Consent
- NIH Patient Bill of Rights
- Legal, Ethical & Safety Issues