Clay Siegall fights cancer, one drug at a time

Clay Siegall is one of America’s foremost medical researchers and biotech entrepreneurs. Over the last 20 years, Siegall has developed some of the most cutting-edge and important treatments in the fight against cancer. Today, his company, Seattle Genetics, leads the fight in the development of a new class of drugs called antibody-drug conjugates.

Clay Siegall first became aware of the brutalities of chemotherapy while still attending college. The treatment often proved worse than the symptoms, with many patients losing their hair, becoming violently ill and even experiencing fatalities. Siegall believed that there must be a better alternative to such a crude and debilitating course of treatment.

He decided to specialize in cancer research. After getting a PhD in genetics from George Washington University in 1988, Siegall went to work for the National Cancer Institute as a medical researcher. After 4 years, he received an offer from Bristol-Myers Squibb as a senior researcher on a cutting-edge new class of drugs known as targeted therapy.

The concept behind targeted therapy was to take the same killer effects of chemotherapy and to deliver them in a way that only targeted cancer cells specifically. There were multiple approaches used to this end. One of those was a class of drugs that Siegall was instrumental in developing. These became known as antibody-drug conjugates.

Antibody-drug conjugates involve developing synthetic antibodies that are meant to attach specifically to the site of a tumor. Cancer-killing agents are bound or conjugated to the antibody which then is introduced into the body and seeks out the site of the tumor. In theory, this can all but eliminate the side effects associated with traditional chemotherapy. Not only does this allow the patient to feel much better, it also allows the therapeutic window to be dramatically increased, allowing for potentially much more lethal loads of drugs to be introduced to the tumor site.

In 1998, Siegall founded Seattle Genetics as a firm specializing in the development and research of this exciting new class of drugs. After overseeing the largest IPO in biotech history, Siegall led his company to develop the first FDA-approved antibody-drug conjugate, ADCeteris. Today, Seattle genetics has eight drugs in the development pipeline and many more licensed for production to other firms. It continues to lead the way in the research of antibody-drug conjugates and may someday find the cure for cancer itself.