experimental drug
Meaning of experimental drug: A medicine still being tested in people, obtainable mainly through a trial rather than an ordinary prescription.
Definition of experimental drug
An experimental drug is a medicine under study in people but not yet approved for sale for the use being tested. It has already passed laboratory and animal testing, and a regulator has permitted human trials to proceed. Its safe dose, its true benefit and its full range of harms are all still being established.
How does a drug reach human testing?
The path is long and most compounds drop out of it. Screening identifies a molecule that acts on a chosen target. Laboratory work refines it and tests it on cells. Animal studies then examine how it is absorbed and cleared, and what damage it causes at high amounts. Only after that can a sponsor ask the Food and Drug Administration, or the equivalent body elsewhere, for permission to give it to people. The application sets out what is known, how the drug is manufactured, and exactly what the first study will do.
What are the phases of testing?
| Phase | Who takes part | Main question |
|---|---|---|
| Phase 1 | A small number of people | Is it tolerated, and at what dose |
| Phase 2 | A larger group with the disease | Does it appear to work |
| Phase 3 | A large group against standard care | Is it better, and how common are harms |
| Phase 4 | After approval | What emerges with wider and longer use |
Rare side effects surface only in the final stage, because a problem occurring in one person in several thousand cannot be detected in a study of a few hundred.
Can anyone receive one outside a trial?
Sometimes. Programs known as expanded access or compassionate use allow an investigational agent to be supplied to a person with a serious illness who has no remaining options and cannot join a study. Agreement is needed from the regulator, the manufacturer and an ethics committee. Supply is never guaranteed, since the quantity available during development is often limited by manufacturing capacity.
What does experimental not mean?
It does not mean unsafe, and it does not mean promising. It means unproven. A few experimental drugs turn out to work better than anything already available. More of them add nothing at all, and a proportion prove harmful in ways that appeared only once people took them. The word experimental records the state of the evidence rather than any judgment about the compound itself.
Also known as
Used in a sentence
The patient was enrolled in a trial of an experimental drug after standard options were exhausted.
Good to know
Experimental means unproven rather than unsafe or promising, and most compounds that enter human testing never reach approval.