Research: Clinical Drug Development and Drug Trials
The U.S. system of new drug approvals is perhaps the most rigorous in the world. It costs millions of dollars to get one new drug from the laboratory to U.S. consumers.
It takes 15 years on average for an experimental drug to travel from lab to U.S. consumers, according to the Tufts Center for the Study of Drug Development, Tufts University, based on drugs approved from 1994 through 1998. Only five in 5,000 compounds that enter preclinical testing make it to human testing. And only one of those five is approved for sale.
Once a new compound has been identified in the laboratory, compounds become medicines as follows:
Preclinical Testing. A pharmaceutical company conducts laboratory and animal studies to show biological activity of the compound against the targeted disease, and the compound is evaluated for safety.
Investigational New Drug Application (IND). After completing preclinical testing, a company files an IND with the U.S. Food and Drug Administration (FDA) to begin to test the drug in people. The IND becomes effective if FDA does not disapprove it within 30 days. The IND shows results of previous experiments; how, it is thought to work in the body; ant toxic effects found in the animal studies; and how the compound is manufactured. Al clinical trials much be reviewed and approved by the Institutional Review Board (IRB) where the trials will be conducted. Progress reports on clinical trials much be submitted at least annually to FDA and the IRB.
Clinical Trials, Phase I. These tests involve about 20 to 100 normal, healthy volunteers. The tests study a drug's safety profile, including the safe dosage range. The studies also determine how a drug is absorbed, distributed, metabolized, and excreted as well as the duration of its action.
Clinical Trails, Phase II. In this phase, controlled trials of approximately 100 to 500 volunteer patients (people with disease) assess a drug's effectiveness.
Clinical Trials, Phase III. This phase usually involves 1,000 to 5,000 patients in clinics and hospitals. Physicians monitor patients closely to confirm efficacy and identify adverse events.
New Drug Application (NDA). Following the completion of all three phases of clinical trials, a company analyzes all of the data and files an NDA with FDA if the data successfully demonstrate both safety and effectiveness. The NDA contains all of the scientific information that the company has gathered. NDAs typically run 100,000 pages or more. By law, FDA is allowed six months to review an NDA.
Approval. Once FDA approves an NDA, the new medicine becomes available for physicians to prescribe. A company must continue to submit periodic reports to FDA, including any cases of adverse reactions and appropriate quality-control records. For some medicines, FDA requires additional trials (Phase IV) to evaluate long-term effects. Discovering and developing safe and effective new medicines is a long, difficult, and expensive process.
For more information you can visit the American Pharmaceutical Companies web site at www.phrma.org Or by mail: Pharmaceutical Research and Manufacturers of America 1100 Fifteenth Street, NW Washington, DC 20005.
