A Stanford University professor and stem cell pioneer whose first job in science paid $25 a month is poised to receive a $191 million windfall from the sale of the immunotherapy biotech firm he co-founded.
Irv Weissman, 80, owns 4.2% of Forty Seven Inc., which Gilead Sciences Inc. agreed to buy for about $4.9 billion, a remarkable amount considering the company’s market value was less than $250 million just five months ago.
Forty Seven is named for a molecule found on healthy and cancerous cells that emits a “don’t eat me” signal that allows cells to go undetected by the immune system. Working in their Stanford lab, Weissman, fellow founder Ravindra Majeti and Siddhartha Jaiswal identified the role of CD47 proteins in the progression of cancer stem cells into a more malignant form.
“The whole system is set up to be able to look at dangerous cells and eat them,” Weissman said in a phone interview. CD47 can interfere with that, allowing cancer to spiral if ignored by the body’s defenses.
The role of CD47 has formed the basis of Menlo Park, California-based Forty Seven’s therapies and research, which focuses in part on blocking signals instructing the immune system to attack, or eat, cancer cells.
Weissman, a native of Great Falls, Montana, is a leader in stem cell research and was the first to identify and isolate blood-forming stem cells from mice.
He became fascinated with science at age 10 after a teacher gave him “Microbe Hunters,” a book about early microbiologists such as Louis Pasteur. In high school he began working in the lab of Ernst Eichwald, a local pathologist. His starting pay: $25 a month.
“He allowed me to act as if I were a grad student,” Weissman said in the interview Thursday. “He was maybe under the delusion that I was a straight-A student.”
Less-than-stellar grades notwithstanding, he learned at the lab that he had “an affinity for discovery.”
After graduating from Montana State College in 1961, he attended Stanford’s medical school, drawn to a curriculum that allowed ample time for research. He’s been there ever since and now heads its Institute for Stem Cell Biology & Regenerative Medicine.