About Clinical Trials
Before new clotting factors can be approved by regulatory agencies such as the Food and Drug Administration (FDA) in the United States, they must undergo a series of research studies called clinical trials. These trials are conducted to determine whether the new clotting factors are safe and effective. Even after FDA approval, clotting factors may still be studied in clinical trials to help answer specific questions about new ways of using them.
Long before new clotting factors are tested in humans, companies conduct laboratory and animal studies to understand their safety and how they might act in specific cells and tissues, and in animals. These studies provide information on:
- Potential side effects
- How the clotting factor is absorbed by the body
- How long the clotting factor stays in the bloodstream
- The therapeutic effect of the clotting factor
After preclinical studies are complete, the company will approach the FDA with a request to progress to testing the clotting factor in people with hemophilia. If approved, the factor goes into Phase 1 testing.
Phase 1/2: Safety
For many conditions and diseases, clinical trials are conducted sequentially, where one phase is completed before starting the next. In hemophilia, however, the phases are typically combined to form Phase 1/2 trials and Phase 2/3 trials. Combining them in this way provides additional information and helps accommodate the smaller population of people with hemophilia.
A Phase 1/2 clinical trial is the first step to study a drug in humans (a clinical trial program). This phase is designed to assess the safety of a clotting factor and outline dosing regimens for future trials. For a clotting factor product to progress to Phase 3, it must meet certain safety standards decided upon at the start of the Phase 1/2 study. Phase 1/2 clinical trials typically include a relatively small number of people.
Phase 2/3: Safety and Efficacy
Phase 2/3 studies are used to determine if the clotting factor is effective and safe. Often, a pharmaceutical company conducts multiple Phase 2/3 trials to study different populations (eg, children or adults) or different uses (eg, prevention of bleeding episodes, resolving a bleed, or use in surgery).
Phase 3 studies are designed to allow the US Food and Drug Administration (FDA) to make an informed decision on a clotting factor's overall safety and effectiveness. A properly designed study will have an appropriate number of participants, a comprehensive safety analysis, and a comparison to either an approved product or a placebo.
After information about safety and effectiveness has been collected in a Phase 3 study, the pharmaceutical company will apply to the FDA to have their clotting factor approved for public use.
Issues specific to the study of hemophilia, such as inhibitor development and safety, are included within these study designs at appropriate and specific phases.
Post-Phase 3 study extensions and Post-Approval Safety Studies are methods to continue to monitor effects over time.
Registries, databases, and other organized collections of information and samples may provide collective information useful to the community and future scientific developments.
To learn more about Biogen Idec Hemophilia's clinical trials investigating the potential of long-lasting recombinant factor VIII (rFVIIIFc) and long-lasting recombinant factor IX (rFIXFc), contact us at 866-MEDINFO or visit www.clinicaltrials.gov and search "rFVIIIFc" or "rFIXFc."