SOUTH SAN FRANCISCO -- Genentech Inc. said its scientists have
produced a synthetic form of rare blood protein used in the
treatment of people who suffer uncontrolled bleeding.
The protein, called Factor VIII, induces clotting in normal
people but is either missing or inactive in people who have
hemophilia, a disease that strikes about one in 25,000 people.
The genetic trait for the ailment is usually carried by mothers
and passed on to their sons.
Currently, hemophiliacs take infusions of Factor VIII to stop
bleeding from wounds or hemorrhaging into their joints, at a
cost of $10,000 to $20,000 a year, Genentech said.
But currently available Factor VIII from such sources as Cutter
Laboratories Inc. is extracted from purchased plasma, made from
blood bought from poor people who are often ill. Thus it
carries a risk of transmitting such blood-borne diseases as
hepatitis and AIDS, acquired immune deficiency syndrome, a
fatal collapse of the body's internal defenses against disease.
The Center for Disease Control in Atlanta has so far documented
30 cases of AIDS traceable to tainted Factor VIII, and recent
publicity has prompted several recalls of the product.
Genentech said that several years of development, animal tests
and human clinical trials must take place before its product is
commercially available, however. Industry souces estimate the
world-wide market for Factor VIII at about $250 million a year.
"We think it's wonderful news," said Alan Brownstein, executive
director of the National Hemophelia Foundation in New York
City. "This carries the potential for safer, more available,
and perhaps cheaper Factor VIII. " Genentech, however,
declined to give any information on its manufacturing or
pricing plans for the substance.
Genentech's work involved isolating and cloning, or
duplicating, the human gene that codes for normal Factor VIII
production. Scientists then put the gene into mammalian cells
and produced what they said was a pure and "biologically
active" Factor VIII. When mixed with blood of hemophiliacs,
this Factor VIII reduced their abnormally long clotting time to
a normal rate of about 60 seconds from 100 seconds.
Genentech said the work involved 30 of its scientists working
for more than a year, in cooperation with the Royal Free
Hospital of London and Speywood Laboratories of Wrexham,