Use of 'single donor' factor VIII from plasma exchange donation
B. C. McLeod and J. P. Scott
We investigated the advantages of using "single donor" factor VIII derived
from a new cyclic apheresis donation (plasma exchange donation) to treat
hemophiliac children. By selecting donors with high factor VIII levels and
using thaw-siphon isolation of cryoprecipitate, we achieved a mean yield of
1,360 units of factor VIII per weekly donation. The half-life,
posttransfusion increments, and clinical efficacy of factor VIII in this
material are comparable with those of factor VIII from other sources. A
single donor has provided total support for seven months for one patient
with severe hemophilia, and another for 24 months for a patient with mild
hemophilia. Other patients have been supported through major surgery or CNS
hemorrhage by a single donor. This approach to factor VIII replacement is
hemostatically effective and can substantially decrease donor exposure for
both major and minor bleeding episodes. The reduction in donor exposure
should result in a reduced risk of acquiring hepatitis and perhaps the
acquired immune deficiency syndrome in patients with hemophilia A.