Rene M. Caisse
Rene M. Caisse was a Canadian nurse who, according to the National Cancer Institute’s own institutional history of the product, obtained a four-herb tea formula in 1922 from a patient who said an Ontario Ojibwa medicine man had given it to her, and who credited it with curing her own breast cancer. Caisse began giving the tea to cancer patients and, in 1934, opened a clinic on Dominion Street in Bracebridge, Ontario, that operated until 1942 and treated cancer patients without charging fees, accepting only donations. She continued providing Essiac to patients into the late 1970s. In 1977 she transferred exclusive commercial rights to the formula to Resperin Corporation Limited. She died in 1978, per her published biography Clinic of Hope: The Story of Rene Caisse and Essiac. That transfer moved the formula from a donation-funded personal practice into corporate ownership. Today, several companies produce and market Essiac-like products.