Two U.S. companies teamed up to treat cancer patients using an unproven blood filter in Antigua, out of reach of American regulators. Two U.S. companies teamed up to treat cancer patients using an unproven blood filter in Antigua, out of reach of American regulators. Cancer, Medical Devices, Blood, Deaths (Fatalities), Regulation and Deregulation of Industry, Private Equity, Start-ups, ExThera Medical Corp, Quadrant Clinical Care LLC, Quadrant Management Inc, Food and Drug Administration, Quasha, Alan, Ilic, Sanja, Antigua and Barbuda, Chow, Dr. Jonathan, John, Dr. Joey NYT > Science