Phase I-IV Rx Clinical Trials

Phase I of an Rx clinical trial was formerly referred to as "first-in-man studies" but was renamed "first-in-human studies" to be gender neutral. These trials are the first stage of testing on human subjects. They were designed to assess the maximum amount of a drug that can be given to a person before adverse effects become dangerous or intolerable.

Once a dose is determined, the next step is to evaluate whether the drug has a biological activity or effect. It evaluates the efficacy and tolerability of the drug when compared to a placebo on those subjects being treated for a disease or condition. Phase II trials are performed on larger groups having 100 to 300 people and are designed to measure how well the drug works. During this time, phase I safety assessments continue for the larger group of patients or subjects.

Phase III of a clinical trial is designed to determine the effectiveness of the drug and its value in clinical practice. These studies are randomized and controlled multicenter trials on large patient groups ranging from 300 to 3,000 subjects and are focused on how effective the drug is compared to the current 'gold standard' treatment. Because of their size and long duration, Phase III trials are the most time-consuming, expensive and difficult trials to design and run. The results of the study usually determine if the drug can be licensed.

Phase IV of a clinical trial is also known as a post marketing surveillance trial or a confirmatory trial. It involves the safety surveillance and technical support of a drug after it receives permission to be sold. It is usually started during the registration and licensing process and continues after the drug is marketed. It is designed to answer additional questions regarding the drug's use and to appropriately position the drug in the marketplace.

IRSI has phase I-IV Rx and OTC trials for clinical indications such as acid indigestion, diabetes, weight loss, constipation, colds, coughs, smoking cessation, pediatric safety testing and odor threshold tolerance.

If you would like additional information about our comprehensive and state-of-the-art services, or to make an appointment to visit our facilities, email sschwartz@irsi.org or ffriscia@irsi.org. You can also call 914-937-9483 or 1-800-548-0158. We are located in Port Chester, NY and are looking forward to hearing from you.