NEW YORK — Ken Koe, a Pfizer Inc. chemist who co-invented Zoloft, which once was the most-prescribed antidepressant drug in the United States, died Oct. 7. He was 90.
He died in Shrewsbury, Mass., at the home of his daughter Kristin, according to Heald & Chiampa Funeral Home. No cause was given.
Approved by the Food and Drug Administration in 1991, Zoloft had sales that peaked at about $3.36 billion for New York-based Pfizer in 2004, two years before its patent ran out.
Zoloft is Pfizer’s brand name for the chemical sertraline hydrochloride, one of a class of drugs known as selective serotonin reuptake inhibitors used to treat depression and anxiety.
Dr. Koe and a fellow Pfizer chemist, Willard Welch, began developing Zoloft in the 1970s. Along with members of their team of scientists at the company, they received an award for innovation from the American Chemical Society in 2006 in recognition of the drug’s impact.
Billie Kenneth Koe was born in Astoria, Ore.
He earned a bachelor’s degree in chemistry from Reed College in Portland in 1945. He earned a master’s degree in chemistry at the University of Washington in 1948 and his Ph.D. at the California Institute of Technology in 1952.
In 1955, Mr. Koe took a position with Pfizer Research Laboratories in New York. He spent 40 years with Pfizer, retiring in 1995 as research adviser in Pfizer’s neuroscience department in Groton, Conn.
In retirement, he served on the planning commission in Ledyard, Conn. His wife, the former Jo Ann Lew, died in 1995.
In addition to his daughter, he leaves another daughter, Karen, and five grandchildren, according to the funeral home.