The Drug Regulatory Process in the United States

Medical writers working in the regulatory environment must know well the process a candidate drug goes through before approval by the FDA. Below is a quick overview of the drug development process.

1. Preclinical Testing

Laboratory tests and animal studies are conducted. These studies show biological activity of the compound in relation to animal models of the targeted human disease or condition. Along with these results, the compound is evaluated for toxicology.

2. Investigational New Drug Application (IND)

An Investigational New Drug Application (IND) is filed with the U.S. Food and Drug Administration (FDA) after completion of preclinical testing. This allows testing of the drug in humans to begin.

3. Phase I Clinical Trials

Small numbers of healthy volunteers are tested with the drug to determine its duration in the bloodstream and the drug’s initial safety profile. This study also provides information about how the drug is absorbed, distributed, metabolized, and excreted in humans.

4. Phase II Clinical Trials

Approximately 100-500 volunteer patients with the disease or condition are tested with the drug to assess its effectiveness.

5. Phase III Clinical Trials

A large number of patients (usually at least 1,000-5,000 subjects) in clinics and hospitals are tested and monitored closely by physicians to confirm efficacy and to identify any adverse effects.

6. New Drug Application (NDA)

If the drug is determined to be safe and effective, an New Drug Application (NDA)
is filed with the FDA at completion of the clinical trials.

7. Drug Approval

Once the FDA approves the NDA, physicians may prescribe the drug to patients.

8. Phase IV

If patients report adverse effects after taking the drug, the FDA may require Phase IV trials to evaluate long-term effects of the product.

The Regulatory Writing Online Course describes this process in depth.