Blood Product to Aid Hemophiliacs Is OKd

Federal officials announced approval on Tuesday of a highly purified blood product developed in La Jolla for treating hemophiliacs--a product expected to substantially decrease patients’ risk of contracting hepatitis, AIDS and other viral infections.

The new concentrate developed at Scripps Clinic and Research Foundation and approved by the U.S. Food and Drug Administration is a highly purified form of Factor VIII, a blood coagulation protein that is deficient in 80% of all hemophiliacs.

“It’s probably one- to three-thousandfold more purified than anything that’s on the market today,” said Dr. Theodore Zimmerman, who is head of Scripps’ division of experimental hemostasis and participated in developing the product.

Hemophilia is an incurable blood-clotting disorder that affects one in 10,000 people worldwide. During bleeding episodes, patients take supplements of Factor VIII, which is extracted from normal blood plasma and makes clotting possible.

Patients Develop Hepatitis

But Factor VIII has been contaminated with viruses that cannot be screened from the blood supply. As a result, the vast majority of people receiving the treatment develop non-A, non-B hepatitis, an untreatable form of the disease that can lead to severe liver problems.

(In addition, as high as 90% of hemophiliacs who received blood concentrates in the early 1980s reportedly appear to have been exposed to the AIDS virus. However, heat treatment of blood products in the last two years has made it possible to screen the AIDS virus out of blood.)

Zimmerman said none of the 17 patients treated with the new product during a three-month period has developed hepatitis. Using other forms of Factor VIII, 60% to 80% of the patients would have contracted hepatitis within three months, he said.

“Purity also prevents the immune system of hemophiliacs from being bombarded with foreign proteins and cellular breakdown products,” Zimmerman said. He said the product may even strengthen the immune systems of hemophiliacs who have been exposed to the AIDS virus.

The new product is to be marketed under the name Monoclate by Armour Pharmaceutical Co., a division of Rorer Group of Fort Washington, Pa. Zimmerman said he expects it will be available next week.

Money to Aid Research

Zimmerman said he could not divulge details of the agreement between Scripps and Armour. However, he said: “Scripps will benefit, but this money will go back into research not just for hemophilia but other illnesses.”

The method of purifying Factor VIII involves exposing plasma to monoclonal antibodies attached to a bed of inert material, Scripps officials said. The antibodies bind and retain the Factor VIII complex while all other materials, including viruses, are washed away.

Pure Factor VIII is then removed from the antibodies, collected, heated, frozen and dried to ensure its stability. Rorer officials say the product is 99.9% pure, contrasted with purity of less than 1% in other commercial Factor VIII products.

Zimmerman, who developed the product with Carol Fulcher of Scripps, said he hopes to see a similar product in the near future for the 20% of hemophiliacs who suffer from a deficiency of Factor IX.