[1] Univ N Carolina, Sch Med, Div Hematol Oncol, Chapel Hill, NC 27514 USA
[2] Univ Hosp Skejby, Dept Clin Immunol, Harmophilia Ctr, Aarhus, Denmark
[3] Univ N Carolina, Sch Med, Ctr Thrombosis & Hemostasis, Chapel Hill, NC USA
[4] Novo Nordisk AS, DK-2820 Gentofte, Denmark
[5] Wayne State Univ, Childrens Hosp Michigan, Sch Med, Detroit, MI USA