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Q of the week

Q: Do clinical trials ever go wrong?

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A test to check for cancer of the cervix, the opening to a woman's womb. It is done by removing cells from the cervix. The cells are then prepared so they can be seen under a microscope.

Phases of Trial
  1. Is a healthy obese person a patient or a volunteer?
    As obesity is not necessarily a disease this depends on the objective of trial.  In a Phase I study a healthy obese person would be a volunteer, in a Phase II, III or IV study a healthy obese person would be a patient.
  2. Is there any difference between Phase IV and other phase studies, is it mandatory to have a study protocol approved by ethics committee for a post-marketing surveillance (PMS) study?
    If this is a regulatory PMS, it is desirable to take approval of Ethics Committee (EC).The need for EC approval also depends on the indications to be studied and proposed study plan.
    Phase IV studies should use the same scientific and ethical standards as applied in pre-marketing studies. After a product has been placed on the market, clinical trials designed to explore new indications, new methods of administration or new combinations, etc are normally considered as trials for new pharmaceutical products.
  3. If any change is done in the formulation of an existing drug, what trial should be trial? Will it be considered as a new drug?
    A change in the formulation makes it a new drug. It will have to conduct trials to get manufacturing permission to market the product. The nature of trial depends on what the sponsor want to establish. Therapeutic equivalence trial is a good option if they wish to compare the approved formulation to a new formulation.
  4. Why Phase I studies are not conducted in female volunteers?
    Usually, the toxicity documentation prior to Phase I does not include reproductive toxicity data. Hence, female subjects with child bearing potential are not included in Phase I.
  5. Can we conduct the Phase IV study in a small number of populations? Is it possible to conduct a comparative study in phase IV?
    Yes, it is acceptable to conduct phase IV as a comparative study if the objectives are scientifically justified. The sample size depends on the objectives and endpoints and has to be statistically valid. ICH E 8 guidelines on general considerations for clinical trials defines phase IV as follows: phase IV (variety of studies: - therapeutic use)
    Phase IV begins after drug approval. Therapeutic use studies go beyond the prior demonstration of the drug's safety, efficacy and dose definition. Studies in phase IV are all studies (other than routine surveillance) performed after drug approval and related to the approved indication. They are studies that were not considered necessary for approval but are often important for optimising the drug's use. They may be of any type but should have valid scientific objectives.
  6. Define Phase 0 studies?
    FDA guidance document, Exploratory IND Studies, offers recommendations about safety testing, manufacturing, and clinical approaches that can be used in very early studies, sometimes called exploratory, or phase 0 trials.
  7. What is Phase II a, Phase II b study?
    Phase II a is clinical pharmacology in patients with target disease (small nos up to 200) to assess pharmacokinetics/ pharmacodynamics and dose/ concentration effect responses for preliminary efficacy and safety, and to validate surrogate endpoints
    Phase II b is a larger scale study in several hundred patients to formally assess the dose response relationship, and continue to expand the efficacy and safety databases

Opinion Poll

Which one of the following do you think is the most common reason for participating in clinical trials?
This opinion poll provides an informal way for the clinical research community to express its views on current topics. The results are not a scientific poll and do not necessarily reflect the percentages of all clinical researchers who agree with these positions.
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