Dr. Zaffaroni, a Uruguayan-born biochemist, started at least 10 companies in Silicon Valley and nurtured other entrepreneurs who started companies. A Silicon Valley legend who played a significant role in the development of the birth control pill, the nicotine patch, the DNA chip and corticosteroids.
He was born on Feb. 27, 1923, in Montevideo, Uruguay, the son of a banker. His mother died when he was 13, and his father died shortly before he turned 18, factors that Dr. Zaffaroni said made him more willing to leave his native country.
After graduating from the University of Montevideo and receiving a Fulbright scholarship to study in the United States, he took a cargo ship to New York in the waning days of World War II. Accepted by Harvard and the University of Rochester, he chose Rochester because it offered him more freedom to choose his research topic.
In 1951 Dr. Zaffaroni went to work for Syntex, a small Mexican company that was isolating a raw material to make steroids from yams. After rising in the organization to become head of research, he helped set up an operation in Palo Alto, Calif., and transform it into a successful pharmaceutical company. It became most known for contributing to the development of the birth control pill. (Syntex was acquired by Roche in 1994.)
Dr. Zaffaroni left Syntex in 1968 to form Alza, which he named after himself by combining the first two letters of his first and last names. Alza nearly went bankrupt in the late 1970s before righting itself. Besides the nicotine patch, it made transdermal patches containing a motion sickness drug, a pain drug and nitroglycerin to treat angina. Other products using its technology include two extended-release pills: Procardia XL, for angina and hypertension, and Concerta, for attention deficit hyperactivity disorder.
Dr. Zaffaroni stepped down as chief executive of Alza in 1987 and from its board in 1998. In the 1980s and ’90s, at an age when many people would retire, he started many companies, including Dnax, Affymax, Symyx Technologies, Maxygen and SurroMed as well as Affymetrix. Some of them applied technology from Silicon Valley’s semiconductor industry to drug discovery and research. Many went public or were acquired by larger companies.
Dr. Zaffaroni and his wife, Lida, established a foundation that has given to various causes, including a breast imaging center at Stanford. In 2006, in honor of Dr. Zaffaroni, Stanford established a $10 million financial aid program for Latin American students; much of the money was donated by people who had worked with him.
Dr. Zaffaroni is survived by his wife; his son, Alejandro; his daughter, Elisa; and two grandchildren.