Clay Siegall takes Seattle Genetics from tiny startups to billion dollar biotech firm

Clay Siegall is CEO and founder of biotech giant Seattle Genetics. Since 1998, Dr. Siegall has led the company with strong leadership and a solid vision, taking the company to the top of the biotech and cancer drug development industry.


Dr. Siegall first became interested in cancer research while attending his graduate studies at the University of Maryland. While pursuing a degree in zoology, Dr. Siegall had a family member who fell sick with cancer. During this ordeal, the family member nearly lost their life. This was not due to the cancer itself. Instead, it was due to the brutal regimen of chemotherapy that was the reigning model for cancer treatment at that time. The family member developed severe anemia and nearly died from shock.


This prompted Dr. Clay Siegall to realize that the state of cancer treatment at that time was far from ideal. This imparted an intense interest in pursuing a career in cancer research and hopefully someday contributing to new treatment models that were not so deadly and ridden with terrible side effects.


Dr. Siegall decided to pursue a degree in genetics. In 1988 he received his doctorate in genetics from George Washington University. Shortly thereafter he was hired by the National Cancer Institute as a junior researcher. There, he worked on an exciting new area of cancer research called targeted cancer therapies. This was a new field of drug development that promised to allow for therapies that would specifically target the tumor site, rather than releasing highly toxic drugs into the bloodstream.


After working for the National Cancer Institute for around four years, Dr. Siegall was hired by Bristol-Myers Squibb as a senior researcher. It was at Bristol-Myers Squibb that he first started working on a revolutionary new type of targeted cancer therapy called antibody drug conjugates. Antibody drug conjugates are a drug class that uses elements of the patient’s immune system to deliver highly toxic chemicals directly to the site of the tumor without any systemic release of the agent into the bloodstream. This dramatically increases the amount of drugs that can be given at any given time. The increased so-called therapeutic window enables oncologists to administer highly lethal doses, leading to much more effective treatments and shorter durations of treatment courses.