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Valerie J. Nelson In an age of rapid medical advances, new plasma products designed to improve the safety of the blood supply are fast approaching the marketplace, and healthcare professionals are cautiously assessing their viability on a large scale. A new blood plasma, approved by the Food and Drug Administration (FDA) in May, has been used with stunning success for more than a dozen years in Europe. Its manufacturer claims the product, Plas+SD (pooled plasma, solvent-detergent treated), will reduce the risk of acquiring a disease via transfusion to zero. Yet the healthcare community is holding back, waiting to fully understand how the controversial pooled plasma works and whether it is necessary, experts say. Another product, donor-retested plasma, also received FDA approval, in September. It entails a higher level of screening, by freezing a donor’s plasma for at least 112 days, then retesting the donor for any new viruses that might have appeared. Healthcare providers are eyeing the technique, questioning whether it merits the higher cost. Though expensive—a pint of either can be at least 2 ½ times the cost of a pint of regular plasma—the new rival plasmas are part of a wave of technology geared toward making the overall blood supply safer. The American Red Cross also is working with the FDA on implementing a blood screening test—genome amplification technology—that would detect the DNA of a virus rather than the antibodies in donor blood, allowing screeners to forecast and predict diseases present at an earlier stage, said Michael Fulwider, a Red Cross spokesperson. The hope is that the "extra layer of safety" would prevent viruses from entering the blood supply, Fulwider said. The new DNA test could be running by early or mid-1999, he said. The Red Cross is the exclusive distributor of Plas+SD, which will replace some of the 2.5 million units of plasma used by tens of thousands of Americans to treat certain diseases such as hemophilia and some liver disorders. Pooled approach Plas+SD gets its name from solvent-detergent washing, a process that inactivates all viruses in the plasma and washes away "lipid-enveloped viruses," which include HIV and hepatitis B and C. It is controversial because the washing requires the pooling of plasma from up to 2,500 donors. Increasing a patient’s exposure to so many donors flies in the face of traditional thinking, experts say. For pooled plasma to receive widespread acceptance, a major shift will have to take place in the way people think about blood products, said Bernard Horowitz, PhD, executive vice president and chief scientific officer of V.I. Technologies in Melville, N.Y., the manufacturer of the solvent-detergent plasma. "What virus inactivation does is provide you with a way of achieving zero risk, despite pooling," Horowitz said.
Solvent-detergent treatment has been used since 1985 on a variety of blood products in Europe without a single reported incidence of transmission of lipid-enveloped viruses, according to Horowitz, one of the inventors of the process. Worldwide, 35 million doses of solvent-detergent treated products have been administered, again without a single report of virus transmission, he added. Cedars-Sinai Medical Center stocks pooled plasma even though there is not yet much demand for it at the Los Angeles facility, said Ellen Klapper, MD, the hospital’s associate director in the division of transfusion medicine. Her department gives presentations to potential major users in the hospital about the benefits of solvent-detergent plasma. "It’s a new product, and they don’t know when to use it," Klapper said. "The benefit is it’s virally inactivated, but the down side is it’s a pooled product. People have a bad taste in their mouths about pooled products. There was so much disease transmission with pooled products in the past, but that’s not the case with virally inactivated products." Horowitz said that education is still needed regarding the components of pooled plasma and that V.I. Technologies is aware that only a small segment of the healthcare community is familiar with the treatment. In addition to advertising in medical journals, the company is supporting scientific symposiums and sending representatives to speak before hospital transfusion committees to explain the process. Donor retesting UC Davis Medical Center has decided against using the pooled plasma, because of the expense and questions of safety due to the large number of donors involved, said Sharon Melberg, MPA, RN, assistant director for hospital and clinics at the medical center. The medical center may turn to donor-retested plasma in "special situations" that have yet to be defined, Melberg said. UC Davis receives 25 percent of its plasma from the Sacramento Blood Center, which is instituting the donor-retested plasma procedures. At least one hospital nationwide is planning to use the donor-retested plasma, but hasn’t yet placed its order, and about 40 facilities have stocked it so far, said Chris Gresens, MD, associate medical director at the Sacramento Medical Foundation Blood Centers in California. He contends donor-retested plasma is a "superior alternative" to solvent-detergent plasma because it’s not a pooled product, which fails to screen for infections caused by non-lipid envelope viruses, such as hepatitis A. The statistics also support donor-retested as a better alternative to regular plasma, Gresens said. In the United States, the risk for getting HIV from a unit of blood is less than 1 in 600,000; the donor-retested approach reduces that risk 20- to 100-fold, Gresens said. The wider acceptance of donor-retested and solvent-detergent plasmas could come in two years or less, Horowitz said. Some countries, including France and Germany, already have banned fresh-frozen plasma for these other "safer" alternatives, he added. Other new approaches to safety plasma are just a "matter of time," Gresens said.
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