Becoming a drug
From initial studies to FDA approval, the process takes about 15 years
Here’s what it takes to get the stamp of approval needed to sell a drug in the United States — a green light from the U.S. Food and Drug Administration.
Test it in the tube
Researchers add the potential drugs one at a time to small batches
of enzymes, cell cultures or cellular substances. Compounds that set off
interesting reactions get further study, including testing for toxicity.
Test it in animals
Before testing the compound in humans,
the FDA requires researchers to assess its effects on animals. And since
a drug might affect one species differently from another, they usually
test it on two or more species — a rodent, such as mice or rats, and a non-rodent, typically a larger animal such as pigs. Researchers measure how much of the compound the animal’s
blood absorbs, how toxic it is and how the body breaks it down chemically
and eliminates it. In some cases, they also run tests extending for several
years to learn whether long-term use causes cancer or birth defects.
Test it in humans
If the potential drug proves safe
in animal trials, the FDA gives the go-ahead for clinical trials — tests
in humans. These tests advance through three phases.
Phase-1 clinical studies: Safety
These relatively small-scale
studies, usually involving 20 to 80 subjects, are designed to reveal
the drug’s metabolic and pharmacologic actions in humans, the side
effects and, if possible, its effectiveness.
Phase-2 clinical studies: Efficacy
This phase of testing
provides preliminary data on the effectiveness of the drug in patients
with the disease or condition and offers additional evidence of the drug’s
short-term side effects and risks. These studies usually involve several
hundred patients.
Phase-3 clinical studies: Safety in numbers
If phase-2 studies appear promising, researchers move on to larger
phase-3 trials, which usually include several hundred to several thousand
people. These provide additional information about effectiveness and safety.
Decision time
The drug company sends the results of
the studies to an FDA committee in the Office of New Drugs that weighs
the compound’s health benefits against health risks. If the benefits
are strong enough, the FDA approves the compound for sale. For drugs
on the high-priority fast-track this takes about six months. For others,
it takes about 15 months.
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