AIDS research pioneer, activist, and amfAR Founding Chairman Mathilde Krim died Monday at her home in Kings Point, New York. She was 91.

As a trailblazing pioneer in AIDS research and activism, Dr. Krim’s philanthropy was present in Hollywood. AmFar hosted a yearly benefit at the Cannes International Film Festival, which was the most successful and coveted events during the fest. She was also married to Arthur B. Krim, a president and chairman of United Artists, founding chairman of Orion Pictures. The two were very active in the American civil rights movement as well as the gay rights movement and numerous other human rights movements. He died in 1994.

“Dr. Krim had such a profound impact on the lives of so many,” said amfAR Chief Executive Officer Kevin Robert Frost in a statement on the organization’s website. “While we all feel a penetrating sadness at the loss of someone we loved so deeply, it is important to remember how much she gave us and the millions for whom she dedicated her life. There is joy to be found in knowing that so many people alive today literally owe their lives to this great woman.”

Dr. Krim was born in Como, Italy on July 9, 1926. She received her Ph.D. in Biology from the University of Geneva, Switzerland in 1953.  From 1953 to 1959, she pursued research in cytogenetics and cancer-causing viruses at the Weizmann Institute of Science in Israel, where she was a member of the team that first developed a method for the prenatal determination of sex.

She was awarded the Presidential Medal of Freedom — the highest civilian honor in the United States — by President Bill Clinton in August 2000 and went on to receive the Award for Greatest Public Service Benefiting the Disadvantaged.

Dr. Krim was the founding chairman and chairman of the board of amfAR from 1990 to 2004. She served as the heart and soul of the organization and was dedicated until to the cause until her health caused her to have a less active role.

She is survived by her daughter Daphna, grandchildren Robert and Amanda and sister Maria. Donations can be sent in lieu of flowers to amfAR, The Foundation for AIDS Research.