experimental
Meaning of experimental: A label describing the setting as much as the substance, since an approved drug becomes experimental again in a new disease.
Definition of experimental
Experimental, in clinical research, describes a treatment or procedure that has completed laboratory testing and been cleared for study in people but is not approved for general use. The term applies to the situation as much as to the product, because a drug licensed for one disease is experimental again the moment it is tested against another.
What makes something experimental?
A compound begins in the laboratory and in animal studies. If those results justify going further, the sponsor applies to the regulator for permission to give it to people. In the United States that permission comes from the Food and Drug Administration, and the application is judged on safety data, manufacturing quality and the proposed study plan. Permission to study is not permission to sell. The product stays experimental until enough evidence accumulates for a licence, and most candidates never reach that point. Failures cluster in the later and costlier stages, which is part of why so few compounds entering human testing ever reach a pharmacy shelf.
Why does the same drug change status?
Approval is granted for a specific use, in a specific group, at a specific dose and by a specific route. Change any one of those and the supporting evidence no longer covers it.
| Situation | Status |
|---|---|
| Approved drug, approved disease and dose | Established treatment |
| Approved drug, different disease | Experimental in that setting |
| Approved drug, new route or schedule | Experimental in that setting |
| Compound never approved anywhere | Experimental |
Prescribing an approved drug outside its licence is common and is called off-label use, which is different from research: it is a treatment decision rather than a study. An experimental drug, by contrast, is normally available only inside a trial.
What protections apply?
Anyone entering research is entitled to know that the treatment is experimental, what is known and unknown about its risks, what alternatives exist, and that refusing or withdrawing carries no penalty. An independent ethics committee reviews the plan before it begins and continues to monitor it. Conduct follows good clinical practice, an international standard covering consent, record keeping, safety reporting and the accuracy of the data collected. Those rules exist because the interests of a study and the interests of an individual taking part are not automatically the same.
Also known as
Used in a sentence
The consent discussion made clear that the treatment offered was experimental and available only within the trial.
Good to know
Permission to study a drug in people is not the same as approval to market it, and an approved drug applied to a different disease is experimental in that setting.
Word origin
Where “experimental” comes from
From the Latin experimentum, meaning a trial or test, formed from experiri, to try.