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Part II - Starting Clinical Trials

by Brendan Milliner and Lisa Rotenstein

Human clinical trials for a particular drug are initiated in volunteers after all laboratory and animal work has been completed and the data have been presented to the regulatory bodies for assessment. Clinical trials are designed to assess the safety, efficacy, and action of a drug in human subjects. Each clinical trial phase asks a different question about the drug.

Phase 1 Trials

A phase 1 trial is the first stage of testing of a drug in people. There are usually two of these trials and they generally involve small groups of healthy people without diabetes (usually 20-80 individuals). They explore what dose of a drug should be given by looking at the safety of different doses. Most of the work is done in a hospital or clinic where health professionals are able to closely monitor the drug's tolerability and mechanism of action in patients (including the speed of action and the drug's interactions with other substances in the body). The first studies start with a single dose of drug; subsequent studies are called multiple dose studies. Volunteers may dose for a period of hours to a couple weeks, depending on the drug. Typically a company can establish a range of doses that are perceived to be sufficiently safe and tolerable for further testing.

Phase 2 Trials

Phase 2 trials typically involve larger groups of participants (about 100-300 individuals), and these participants usually have the condition the drug is intended to treat (for Symlin, it was diabetes). They look to see how well the drug works for its specified purpose, and data are still collected about the drug's safety. This is the first time the company sees whether the drug works as planned, but also the first time when a drug can fail based on a lack of efficacy. This type of trial examines several potential doses of the drug within the range identified in phase 1 to determine at which dose levels the drug is efficacious. These trials are still usually held in a limited number of locations.

One of Symlin's phase 2 studies took place specifically in adolescents. It looked at the drug's pharmacokinetics and pharmacodynamics (how the drug works in the body), and safety and tolerability o f the drug in patients 12 to 17 years old at 3 sites—in Aurora, CO, Kansas City, MO, and New York, NY. It tested two different doses of Symlin (15 and 30 mcg) and determined that they were safe and efficient in teen patients.

The End of the Process, Some More Testing, then Soon to Market!... In the Next Segment!

November 2009


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Last Updated: Wednesday December 31, 2014 20:55:36
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