Phases of Clinical Research

From the Editor…

To our knowledge, no clinical trials are currently underway regarding pityriasis rubra pilaris and any pharmaceutical in the pipeline. However, there is ongoing clinical and genetic research at Thomas Jefferson UnIversity.

We need to foster more research. Perhaps the PRP community could ask PRP-savvy dermatologists to consider independent, case studies regarding the efficacy of treatment options, e.g., retinoids versus immunosuppressants versus biologicals.

The Food and Drug Administration (FDA) has described five phases of a clinical trial of a drug based on the study’s characteristics, such as the objective and number of participants. Perhaps the PRP community should adopt the spirit of “Phase 2″ and become advocates of studies that gather preliminary data on effectiveness”. There are two possible titles for such research:

(1)  PRP Efficacy Research
(2) What-works-and-what-doesn’t-work Research

For the record, here are the FDA’s five phases of clinical research.

Phase 0
Exploratory study involving very limited human exposure to the drug, with no therapeutic or diagnostic goals (for example, screening studies, microdose studies)

Phase 1
Studies that are usually conducted with healthy volunteers and that emphasize safety. The goal is to find out what the drug’s most frequent and serious adverse events are and, often, how the drug is metabolized and excreted.

Phase 2
Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition). For example, participants receiving the drug may be compared to similar participants receiving a different treatment, usually an inactive substance, called a placebo, or a different drug. Safety continues to be evaluated, and short-term adverse events are studied.

Phase 3
Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4
Studies occurring after FDA has approved a drug for marketing. These including postmarket requirement and commitment studies that are required of or agreed to by the study sponsor. These studies gather additional information about a drug’s safety, efficacy, or optimal use.

06.01.09  Phases of Clinical Research

One Reply to “Phases of Clinical Research”

  1. Another two types of studies that may be relevant to PRP are longitudinal or retrospective studies and meta-analyses. (I wish I remembered more about all this, but it’s been years since I had to have this knowledge at my fingertips.)

    Retrospective studies take a group of people (a cohort) with similarities (such as the fact we have PRP) and look back at what differences we have. This is a way to study smaller cohorts or multiple factors–like which environmental exposures have we had or what drugs worked. This is a back-ward looking study as opposed to clinical trials which follow a set of patients over time. I believe this is the type of thing TJU is doing with Stelara.

    Meta-analysis is a statistical method to look at many studies, large and small, and combine their data. This studies that can be analyzed can span decades and can take place anywhere in the world, so combined the analysis will involve many more patients than would be studied in a clinical trial.

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