A prospective study of treatment of acquired (autoimmune) factor VIII inhibitors with high-dose intravenous gammaglobulin.
A decrease in inhibitor titer has been reported in some patients with acquired factor VIII inhibitors treated with intravenous gammaglobulin (IGIV). We have conducted a prospective, multicenter study of high-dose IGIV in treatment of this disorder to determine efficacy. Nineteen patients received induction therapy with IGIV, 1,000 mg/kg x 2 consecutive days or 400 mg/kg x 5 consecutive days, followed by maintenance doses at intervals as clinically indicated. A > or = 25% reduction in inhibitor titer was observed in 8 of 16 assessable patients, six of whom met the criteria for response. A rapid decline in inhibitor titer over 3 to 4 days was observed in two patients, but in four additional responding patients--two of whom received repetitive maintenance doses of IGIV--the decline was more gradual, with final nadirs being reached several weeks to many months after treatment. The inhibitor disappeared in three patients with low-level inhibitors, less than 1 Bethesda unit (BU). Concomitant therapy with prednisone may have contributed to the response in two of the patients but was not a factor in four patients; the response rate is, therefore, estimated to be between 25% and 37.5%. These results confirm the beneficial effect of IGIV in treatment of some patients with acquired autoimmune factor VIII inhibitors.
Schwartz
R S
RS
Department of Clinical Research, Miles Inc., Berkeley, CA 94710, USA.
Gabriel
D A
DA
Aledort
L M
LM
Green
D
D
Kessler
C M
CM
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000276:immunology*; D001327:Autoimmune Diseases / Q000276:immunology / Q000628:therapy*; D005169:Factor VIII / Q000037:antagonists & inhibitors* / Q000276:immunology; D005260:Female; D006467:Hemophilia A / Q000276:immunology / Q000628:therapy*; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000276:immunology / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome
D001323:Autoantibodies; D016756:Immunoglobulins, Intravenous; D005169:Factor VIII