December 11, 2000
Emory fights hemophilia
on many fronts,
improving patient lives
By Holly Korschun
The comprehensive hemophilia program at Emory has become a national leader
in research and treatment programs that are helping improve the lives
of the 15,000 hemophiliacs living in the U.S. Although these patients can now enjoy a normal lifespan, they must rely on infusions to treat frequent bleeding episodes, then cope with resulting complications, including inhibitors that can render the infusions ineffective as well as the threat of infections and joint diseases caused by internal bleeding. In the past, the cure for hemophilia has sometimes been worse than the
disease. In the past, Factor VIII products to treat hemophilia patients were made
by concentrating clotting factor gathered from the plasma of a large group
of donors. In the mid-1980s, when scientists discovered that these blood
products could transmit diseases like HIV and hepatitis C, they began
heating Factor VIII products to kill these viruses. In the early 1990s, scientists carried safety one step further with genetically
engineered recombinant Factor VIII products, made by inserting the Factor
VIII gene into a cell line and producing mass quantities of concentrated
human Factor VIII. Although these products contained no human or animal products, they were
stabilized with a small amount of albumin, a human blood component. Kogenate
FSthe newest FDA-approved productuses small amounts
of albumin in the initial fermenting solution, but in the
final stage, albumin is removed, leaving the product almost completely
free of any human or animal components. Our research found that the new product works just as well as the
current products and appears to offer a greater safety margin against
infectious agents, said Thomas Abshire, medical director of Emorys
hemophilia program and one of the principal investigators for the study. Emory has just completed another randomized study, in collaboration with
the American Red Cross, in which hemophilia patients with hepatitis C
were treated either with a combination of interferon (the known treatment)
and Ribavirin, or with interferon alone. Preliminary results determined
that the combination therapy is better. Emory also is a world leader in treating joint disease in hemophiliacsa
common problem caused by bleeding into joints, which causes irritation
in the lining of the joint cavity and creates a cycle of bleeding and
inflammation. Surgeons and hematologists have collaborated on a study
of arthroscopic synovectomy, in which a small endoscope is inserted into
the ankle, elbow or knee to clean out the thickened lining. When surgery is not an option, physicians use an alternative technique
to inject a radioisotope into the joint that eliminates the abnormal lining.
Michael Busch and Amy Dunn coordinate this program. Emorys comprehensive adult and pediatric hemophilia program includes hematologists, infectious disease specialists, hepatologists, orthopaedic surgeons, physical therapists and specialty nurses. The program receives some federal funding through the Maternal and Child Health Bureau (MCHB) and the Centers for Disease Control and Prevention (CDC). Two adult and two pediatric hematologists treat 350 patients, including 140 children, and the staff also works closely with a program at Childrens Healthcare of Atlanta at Scottish Rite that treats 150
additional children. Abshire also is medical director for MCHB Region
IV South hemophilia programs that include Alabama, Mississippi, Georgia
and Florida. Although the number of hemophilia patients is small relative to many
other diseases, it commands a great deal of attention because it is so
expensive to treat. For example, clotting factor for a mild joint bleed
in a typical 7-year-old child, even at reduced rates, averages $600 per
infusion, with some patients needing several infusions per week. There is a motivation to produce a better product and one you can
use less of, which may come with the eventual development of gene therapy
for Factor VIII, Abshire said. Other current clinical trials at Emory aimed at treating bleeding disorders
and their complications include: (1) a study of children who experience
clotting problems from permanent IVs; (2) a CDC-sponsored study designed
to identify and treat women with undiagnosed bleeding disorders who are
experiencing abnormal bleeding with menstrual periods (hematologist Sidney
Stein leads the Emory component of this multisite study); (3) multiple
clinical trials designed to evaluate the safety and efficacy of new products
used to treat bleeding episodes; (4) multiple AIDS Clinical Trials Group
(ACTG) studies for patients who contracted HIV infection from blood products
prior to the development of safer products. Exciting research advances are on the horizon to deal with the problems faced by the 20 percent of hemophilia patients who have antibodies that inhibit the effectiveness of substitute Factor VIII products. For instance, Emory hematologist Pete Lollar is conducting research that includes gene therapy and an improved Factor VIII molecule constructed from a combination of human and pig Factor VIII genes. |