Jan. 25, 1922

Dr John G. FitzGerald, Director of Connaught Antoxin Laboratories, offers Banting, Best and Collip the use of Connaught’s lab facilities. Work begins to develop methods to produce a purified extract for clinical trials.

Jan. 23, 1922

Collip works day and night for 12 days to improve the extract, and Leonard is given a second dose that is completely successful, with no obvious side-effects and completely eliminates the glycosuria sign of diabetes.

Jan. 11, 1922

Leonard Thompson, a 14-year-old diabetic lies dying at the Toronto General Hospital, is given the first injection of insulin. However, the extract is so impure, Thompson suffers a severe allergic reaction, and further injections are canceled.