Clay Siegall, the cancer innovator and founder of Seattle Genetics, has spent a lifetime searching for novel cancer therapies that someday may lead to what’s known in the business as the c word, a bona fide cure. With over 15 years as a researcher and nearly 20 as a CEO of his own firm, Dr. Siegall is one of the world’s foremost cancer experts and will be one of the key players to watch in the coming decades of cancer research.
A new therapy for an ancient scourge
Dr. Siegall was first drawn to cancer research when he was made aware for the first time, as a college student, of the barbaric and sometimes lethal treatments for many different types of cancer. Ranging from horrific, like the nausea-inducing and completely debilitating metal-based chemotherapies, to the ghastly, like the various radical surgical techniques which involve amputations and other grievous excisions, the orthodoxy of cancer treatment leaves the worst excesses of the Inquisition to want for brutality.
After working as a cancer researcher for 15 years, Dr. Siegall discovered a new class of drugs that promised an end to all that was diabolic about cancer treatment. These were called the antibody drug conjugates.
The principle behind them is startlingly simple. An antibody drug conjugate binds a cytotoxin, something that kills cells, to an antibody, which in this context is a kind of enzyme which binds to a particular molecule in the tumor. Once bound to the tumor, the antibody portion, which is conjugated, or linked, to the cytotoxin portion, releases the cytotoxin into the cellular environment, causing the immediate death of the cell in question and, in some cases, other neighboring cells.
What’s so revolutionary about these drugs is that they only target tumor cells. In the case of Seattle Genetics’ first FDA approved drug, Adcetris, the antibody targets a gene which is expressed specifically and only in Hodgkin lymphoma cells. Thus, there is no systemic release of the cytotoxin, as occurs in traditional chemotherapy. This reduces the side effects of treatment to almost nothing while vastly increasing the lethality to the malignancy.