An extra margin of safety is now available to
the approximately 400,000 people in the US who receive transfusions
of blood plasma annually. PLAS+SD (Pooled Plasma, Solvent/Detergent
Treated) is an FDA-approved product that virtually eliminates
specific viruses in the plasma component of the blood. PLAS+SD will
be marketed by the American Red Cross and manufactured and
distributed by V. I. Technologies, Inc., the developers of the new,
specially treated pooled plasma.
"The American Red Cross is continually researching, developing,
and implementing new testing and treatment methods to ensure the
greatest possible protection of our nations blood supply,"
said American Red Cross president Elizabeth Dole. "The US blood
supply is safer than ever before, and we are proud to introduce an
added layer of protection with PLAS+SD, the first virus-inactivated
blood plasma product," she said.
Special Process Reduces Virus Transmission
The increased protection afforded by PLAS+SD is due to a special
process called solvent-detergent treatment. This process dissolves
the lipid coating of certain viruses that may be present in the
blood, while leaving needed plasma proteins, such as fibrinogen and
immunoglobulins, intact. Clinical studies show that solvent-detergent
treatment reduces the risk of transmitting lipid-enveloped viruses,
including those responsible for AIDS (HIV, or human immunodeficiency
virus), hepatitis B (HBV), and hepatitis C (HCV).
Approximately 4 million people each year receive blood or blood
products as part of their medical or surgical care. Blood banks today
practice two methods to safeguard the supply--screening of the donor
and viral testing of donations--to reduce the transmission of virally
infected blood. However, the risk of transmission of viral infection
through blood transfusion remains because of donations of blood
during the infectious "window period." Currently, a window
period exists between the time a blood donor contracts an infectious
disease and its detection by standard serologic tests--thus
heightening the risk of blood from infectious donors appearing in the
Improved screening tests that shorten the window periods for HIV,
HBV, and HCV will reduce the risk of transfusion-acquired infections
but will not completely eliminate the residual risk of infection from
these viruses. In addition, there are viruses and possibly new
strains of viruses that are not routinely screened.
"Our vision is to eliminate the risk of blood-borne pathogens in
the US blood supply through the use of viral inactivation
technologies," said Bernard Horowitz, MD, executive vice
president and chief scientific officer of V. I. Technologies.
"The approval of PLAS+SD is another key step in closing the
window of viral infection completely." Dr. Horowitz led the team
that developed the solvent-detergent process while employed at the
New York Blood Center.
Indications for PLAS+SD
The indications for PLAS+SD are the same as for fresh frozen plasma
(FFP). Specifically, PLAS+SD is indicated for the treatment of
patients with documented deficiencies of coagulation factors for
which there are no concentrate preparations available, including
congenital single-factor deficiencies of factors I, V, VII, XI, and
XIII. The new product is also indicated for the treatment of patients
with acquired multiple coagulation factor deficiencies, reversal of
warfarin effect, and patients with chronic relapsing or acute
thrombotic thrombocytopenic purpura.
The method of SD treatment adapted for plasma involves the incubation
of pooled thawed plasma from volunteer donors with the organic
solvent tri(n-butyl)phosphate (TNBP) and the detergent Triton X-100.
Since PLAS+SD is a pooled product, it offers the advantage of
relatively uniform protein composition from lot to lot. It is also
sterile-filtered to eliminate bacteria and intact leukocytes.
"Certain people with coagulation disorders will especially
benefit," said Chris Lamb, vice president of plasma operations
for the American Red Cross. "The benefits, in addition to viral
inactivation, are sterile filtration and uniformity of product."
"The American Red Cross will use its national network to make
PLAS+SD available to all US community blood centers, blood banks,
hospitals and transfusion centers as quickly as possible." Mr.