The first treatment for Rh disease was an exchange transfusion, which was invented by Dr. Alexander S. Wiener and later refined by Dr. Harry Wallerstein. Approximately 50,000 infants received this treatment. However, this could only treat the disease after it took root and did not do anything to prevent the disease. In 1960, Ronald Finn, in Liverpool, England proposed that the disease might be prevented by injecting the at-risk mother with an antibody against fetal red blood cells (anti-RhD). Nearly simultaneously, Dr. William Pollack, an immunologist and protein chemist at Ortho Pharmaceutical Corporation, and Dr. John Gorman (blood bank director at Columbia-Presbyterian) with Dr. Vincent Freda (an obstetrician at Columbia-Presbyterian Medical Center), came to the same realization in New York City. The three of them set out to prove it by injecting a group of male prisoners at Sing Sing Correctional Facility with antibody provided by Ortho, obtained by a fractionation technique developed by Pollack.