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The Long way to Approval of a new drug

Different type 2 drugs are in dif¬ferent stages of development. Each product must go through clinical trials before the company submits an application to the U.S.

Food and Drug Administration / (FDA) for approval. In general, for every 5,000 substances drug companies consider, only about five actually enter clinical trials. Of those five, the FDA will approve only one.

Preclinical testing. This is the first consideration of a new drug. The company evaluates how a given substance works in test tubes and laboratory ani¬mals. It takes from 3 to 3V2 years for most companies to decide whether to pursue further testing.

Investigational new drug application (lND application). After the company determines that preclinical testing was successful, it will file an IND application with the FDA. Then clinical trials may begin.

Fase I. This phase determines the safety and dosage of the drug. There are usually between 20 and 80 healthy volunteers in the trial who do not have the condition the drug is meant to treat. Phase 1 trial last for 1 year.

Fase II. The second phase of clinical trials involves between 100 and 300 volunteers who have the condition the drug is meant to treat. Researchers evaluate the drug's effectiveness and look for side effects. This phase lasts about 2 years.

Fase III. In the third phase, researchers evaluate the drug's effectiveness in 1,000 to 3,000 volunteers who have the condi¬tion the drug is meant to treat. This phase takes about 3 years and gives researchers a chance to see if there are any adverse effects from long-term use.

New drug application (NDA). If a drug company is satisfied that its product is safe and effective, it will file an NDA with the FDA to request approval to see the drug in the United States. Review may take as long as 2Y2 years, unless the FDA decides to "fast-track" the drug. When a drug is fast-tracked, it has priority review, and the FDA may render a decision in as little as 6 months.

Fase IV. In the final phase, also known as the post-marketing phase, the company tracks the drug once it's out on the market.

All this safety measures are needed in order to protect our health. Sometimes even with all this safety controls and studies some drugs must be withdrawed from the market for severe and previously unknown risk for your health, recently in our speciality it happened with two marketed drugs:
The first available glitazone: troglitazone, from Parkes Davis, and the cholesterol fighting agent: cerivastatin, from Bayer.
Ramiro Antuña de Alaiz
Educational Treatment Unit
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