ARMOUR DDAVP (DESMOPRESSIN) PROTOCOL FOR INCREASING FACTOR VIII

ARMOUR DDAVP (DESMOPRESSIN) PROTOCOL FOR INCREASING FACTOR VIII levels in blood donors will be discussed by the Rorer subsidiary and FDA. "We thought that this might be an opportune point in time to try to see if we could develop a reasonable protocol under an IND" for desmopressin, Armour VP-Scientific Affairs Michael Rodell, PhD, informed FDA's Blood Products Advisory Committee at its May 10 meeting. Rodell expressed Armour's interest in the new indication following a presentation by the FDA Blood and Blood Products Division's John Finlayson, PhD, chief of the hepatitis lab. Finlayson outlined new potential indications for DDAVP, including use in stimulating donors for source plasma and use in increasing factor VIII levels in directed donors whose factor VIII concentrate would go to a specific hemophiliac. He noted that reports from Sweden indicate that the fraction one zero [the material concentrated with factor VIII] from DDAVP-stimulated donors "had about a one-and-a-half-fold to two-fold increase in its factor VIII content, compared to the fraction one zero of the same donors not stimulated with DDAVP." Rodell said Armour has been interested in the indication for about eight years. He indicated that interest in the new indication has been renewed because the products currently available to treat hemophilia are "greatly purified, but they result in tremendous yield losses because of this purification." He continued: "Maybe there are ways and means that we can hype up or increase the amount of AHF that comes in the pipeline by being able to utilize donor-stimulation programs." Finlayson stressed that there are many questions that still need to be answered, including: how often donors should be stimulated?; how donor safety will be demonstrated?; and is DDAVP stimulated plasma different from other plasma in any other respects? Desmopressin is currently indicated for hemophilia A, von Willebrand's disease (Type I), diabetes insipidus, and for temporary polyuria and polydipsia following head trauma or surgery. The FDA Blood and Blood Products Division's Cellular Biology Lab Chief Thomas Hoffman, MD, provided the panel with an update on the number of IND submissions for monoclonal antibody-based products. "In 1989, through the first quarter, the number of submissions is averaging approximately two per week, which would mean approximately 100 new original submissions for [the products] in this year alone," he noted. In working with human monoclonal antibodies, Hoffman said his lab "found that certain of the human EBD-transformed lines that we were working with had HIV sequences that were detected by polymerase chain reaction." He continued: "I don't think that too many people know about this yet, but it poses an interesting question: 'Do we ask the manufacturers of human monoclonals to look for HIV sequence by polymerase chain reaction?'"