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Part I - Introduction and the Beginning of the Process

by Brendan Milliner and Lisa Rotenstein

You will sometimes hear about drugs that are "not yet approved", "at the FDA" or "in the regulatory process." Some recent approvals of diabetes drugs in the US have stirred some controversy, and we think it's important for our readers to understand the basics of how drugs are discovered and approved. In this issue of Learning Curve, we'll take you through the development and regulatory process for drugs. As an example, we'll be following Symlin, a drug approved in 2005 that mimics the human hormone amylin. It helps lower blood sugar levels after meals. We bet lots of you, in fact, have either heard of or use Symlin!

The topic of drug approval is pretty timely because there are a number of drugs currently before the FDA in the US and other regulatory agencies around the world - just to name a few, liraglutide, exenatide once-weekly, saxagliptin, alogliptin, and Afresa inhaled insulin are all at the FDA now, waiting for a decision. These are all compounds that could significantly move forward diabetes care! Although these are drugs for adults for the most part and for type 2 for the most part, we also watch closely drugs for type 1 outside insulin – Symlin is one example, and dapagliflozin (still in development, now in phase 3), is another!

Preclinical Studies

Many older drugs were discovered by accident, when somebody realized incidentally that a substance had a therapeutic effect. Today, most diabetes drug development follows a more linear track. First, researchers identify a "target" - something in the body that if acted on will have a positive effect. This something could be a protein, a chemical reaction, or a biological process that when altered by treatment, helps improve a person's condition. Next, the pharmaceutical industry works to develop a drug - usually a compound that is made by chemists, but sometimes a "biologic" that is made by living cells - that will act on this target.

Before this new drug can be evaluated in people, it must first be tested for safety and effectiveness in test tubes and in animals. These non-human studies are called "preclinical studies." The kinds of cells or animals used for these trials varies depending on the type of compound used, how it will be administered (as an injection, a pill, etc.), and which part of the body it is designed to affect. Many trials of diabetes medications are done in mice, which can be genetically manipulated to show symptoms of the disease being studied and are easy to care for, and primates, which are biologically much more similar to humans.

The types of preclinical trials conducted with animals can vary quite a bit as well, but the primary goal is to establish that the drug is both effective enough to warrant human study and safe enough that human volunteers won't be putting themselves in serious danger. Studies in animals also test to make sure the compound won't cause cancer or mutations, damage an embryo or fetus, or have other harmful side effects. By giving animals such as mice very high concentrations of a potential drug, researchers can find the limits of safety so that they don't accidentally give a dangerous dose to a human subject. Mouse models are also often used to simulate human diseases.

Starting Clinical Trials ... In the Next Segment!

November 2009


This story is brought to you by diaTribe, an independent, advertising free, e-newsletter focused exclusively on products and research for people with diabetes. Jeff Hitchcock has been on diaTribe's advisory board since its inception. Kelly Close, the editor-in-chief, has had type 1 for nearly 25 years. diaTribe is for everyone eager to learn about the latest advances in diabetes management focusing on research and product news.

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