Glenn Laken

Clay Siegall uses precision medicine to bring innovative new cancer treatments to market

Over the past 30 years, the cancer industry has seen some of the most exciting developments take place in the history of medicine. One of these has been the advent of what’s known as precision medicine, a sub-discipline of drug research that seeks to create drugs and other treatments that are able to specifically target disease sites, potentially leading to far fewer side effects and increased effectiveness. One type of precision medicine research that has yielded tremendous results so far has been the development of a class of drugs known as antibody drug conjugates.

Antibody drug conjugates are the development are primarily one man, Clay Siegall. After becoming one of the nation’s foremost cancer researchers throughout the 1980s and 1990s, Clay Siegall began working on a totally unprecedented class of drugs while still at Bristol-Myers Squibb. Working as a senior researcher, he led his team to develop one of the most innovative drug manufacturing processes of the world has ever seen. Using malignant tissue, Dr. Clay Siegall was able to inject the cancer cells into the bodies of mice, which then produce antibodies. These antibodies were the mammalian body’s way of specifically targeting the malignant tissues. Unfortunately, the body’s ability to fight malignant tissue through the production of antibodies is severely limited and in many cases non-existant. However, the antibodies are still extremely effective at seeking out and attaching to the malignant tissue, making them a useful delivery mechanism for more lethal agents.

Dr. Siegall’s insight was that these antibodies could be improved upon through highly sophisticated means of producing synthetic molecules that were nearly but not quite identical to them. Through this process, it became possible to devise molecules that function as the natural antibodies produced by the body but that were far less likely to induce adverse reactions in actual patients’ bodies, such as anaphylaxis or other allergic reactions.

Once the optimal antibody for a given type of malignant tissue was developed, Dr. Siegall and his team were then able to bind a cytotoxin to the antibody, creating a system whereby the cytotoxin would be delivered directly to the surface of the tumor, not being released until the malignant tissue was reached.