Phase II clinical Trial
Definition:
A Phase II clinical trial is the next phase in the drug approval process following completion of Phase I studies. Once the Phase I trial is completed, researchers then administer the treatment, this time to patients (as most phase I studies are conducted in small groups of healthy adult volunteers) based on the dosing and safety information gathered from the Phase I trial. Phase II clinical trials typically include approximately 100-300 people, with a goal of determining effectiveness and insights on the drug’s safety profile in patients with the condition of interest.
Relevance:
Phase II clinical trials are essential as they further elucidate the safety and efficacy of a drug in a larger group of patients (in comparison with Phase I trials).
Phase II trials help determine if new drugs and therapeutics are sufficiently efficacious and safe to progress to larger scale phase III trials.
Phase II clinical trials enrol patients (as opposed to healthy individuals, as that is commonly done in Phase I).
A larger group of patients are usually treated with the dose determined to be most effective and safe.
Patients may be divided into different groups, depending on the dose received (treatment groups) to further understand the efficacy and safety profile of the drug/treatment.
The main objectives are to confirm safety of the drug, especially in patients, and to obtain an estimate of its effect.
Teaching Tips:
Why do Researchers do Different Kinds of Clinical Studies? https://www.nih.gov/sites/default/files/health-info/clinical-trials/infographic-why-researchers-different-kinds-clinical-studies.pdf
What is Clinical Research? — YouTube(link is external)
Types and Phases of Clinical Trials: https://www.cancer.org/cancer/managing-cancer/making-treatment-decisions/clinical-trials/what-you-need-to-know/phases-of-clinical-trials.html
https://experientialmodules.utoronto.ca/wp-content/uploads/articulate_uploads/Drug-Development/story.html
Linked terms: Phase I clinical trial, Phase II clinical trial, Placebo, Titration, Efficacy, LOAEL (Lowest Observed Adverse Effect Level), NOAEL (No Observed Adverse Effect Level)
Resources:
U.S. Department of Health and Human Services. (2022, October 3). The basics. National Institutes of Health. https://www.nih.gov/health-information/nih-clinical-research-trials-you/basics#:~:text=Phase%20I%20trials%3A%20Researchers%20test,safety%20and%20identify%20side%20effects
Torres-Saavedra, P. A., & Winter, K. A. (2022). An Overview of Phase 2 Clinical Trial Designs. International Journal of Radiation Oncology, Biology, Physics, 112(1), 22–29. https://doi.org/10.1016/j.ijrobp.2021.07.1700
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