The Banting Research Foundation funded the first clinical trials of heparin in 1935. Heparin is a powerful anticoagulant that is widely used in open-heart and organ transplant surgery to prevent the formation of blood clots. It was purified in the early 1930s in Toronto under the direction of Dr Charles H Best. It was then tested by Dr Gordon Murray, a prominent surgeon at Toronto General Hospital, and his colleagues, in human trials beginning in May 1935.
Heparin is a naturally occurring molecule that prevents blood from clotting. It was discovered in 1916, but until 1933 was only available in small quantities that were expensive and toxic to humans. Best and his team at Connaught Laboratories took up the challenge to make it clinically useful, and by 1935 were able to inexpensively produce safe and nontoxic heparin. In May 1935, Dr Murray and his surgical team began the first human trials of heparin at Toronto General Hospital. The Banting Research Foundation provided grants to Gordon Murray, TS Perrett, Frederick R Wilkinson, and Ross G Mackenzie from 1935 to 1939 to establish the safety and effectiveness of heparin.
Over the following years, heparin allowed ground-breaking research that enabled adults (Wilfred G Bigelow) and children (William T Mustard) to undergo open heart surgery safely and effectively. Remarkably, heparin and its successor molecules remain cornerstones of contemporary medical therapy, and the technically challenging operations these surgeons pioneered are now considered routine.