A Cliff's Guide to the Phases of Clinical Trials

Your 1-page guide to clinical trial phases

There are a number of clinical trials and scientific studies underway testing the effectiveness of cord blood and cord tissue in the treatment of various conditions. The various kinds and phases of these studies can be a bit confusing but do give insight into what the study is striving to prove at each point in the process toward full FDA approval. Here's your Cliff’s guide to clinical trials:

Animal study

When researchers believe that cord blood or cord tissue could prove to be a viable treatment for certain conditions, they may conduct tests on lab mice to study how safe the treatment is and how well the it works at different doses. As outcomes in mice may not necessarily translate to humans and should be taken with a grain of salt, it often only serves as a jumping off point and good way to show proof of concept and safety.

Phase I clinical trial

Phase I clinical trials are normally kept small, to around 10 people, and are used to show that the treatment is safe in humans and to monitor any side effects. Many phase I clinical trials will report the treatment outcomes as a sort of sneak peek at how well the treatment performs and drum up interest in the study, but because it is conducted with few participants, the outcome cannot be extrapolated to the public.

Phase II clinical trial

If the treatment is safe and shows signs of being effective, it will often move on to a phase II clinical trial. This is to really test the effectiveness of the treatment in humans and to see what doses or protocol work best. It is often performed in a much large subsection (between 25 and 100 people).

To make sure the participants do not alter the outcome because of the placebo effect, these studies many be blinded, which means the participants do not know if they are part of the control group or the treatment group. In many cases where a treatment like cord blood or cord tissue is being studied to treat a rare or hard-to-treat condition, the control group will often be allowed to also recieve the treatment after a given amount of time.

To ensure the researchers themselves do not effect the outcome of the treatment group, the study may be double-blinded, which means neither the participants nor the researchers know who is part of the treatment group and who is part of the control group.

Phase III clinical trial

If the treatment has shown to be safe and effective, the study will move to a phase III trial. This is designed to test how well the treatment compares against current standard treatments. This is preferably performed with more than 100 participants. Phase III trials are often randomized and double-blinded.

After the third phase, the FDA will review and approve if the drug shows an improvement over current therapies.

Phase IV

Phase IV is not a clinical trial, but more of a post-approval monitoring performed by the FDA if they need to answer any more questions regarding the new drug, such as quality of life or cost impact.

Last Updated on: 04/26/2018 by Valeria Arcila