Effect of interferon (IFN) on refractory idiopathic thrombocytopenic purpura: administration of 6 million units of recombinant IFN alpha-2b.
Five patients (six courses) with refractory idiopathic thrombocytopenic purpura (ITP) were given 6 million units of recombinant interferon (IFN) alpha-2b in 12 doses to achieve an improved response rate compared to previous studies using 3 million units. From the initial IFN administration, the platelet count increased from a pre-treatment level of 20.7 +/- 17.7 x 10(3)/microliters (mean +/- SD) and reached its first peak in weeks 2 or 3 of therapy (p < 0.05). In week 5, the platelet count made its second and maximum peak (66.5 +/- 57.9 x 10(3)/microliters; p < 0.05). A relatively good response of the platelet count (an increase to > 50 x 10(3)/microliters) was observed in three patients (four courses) out of five. These responses were not much faster or more improved than in previous reports, and a dose of 6 million units may be too large to treat some ITP patients. The platelet-associated IgG level showed a tendency to be reduced with IFN therapy. The mechanism for the increase of the platelet count may be the modification of platelet autoantibody production.
Ishii
H
H
Second Department of Internal Medicine, Chiba University School of Medicine, Japan.
Oh
H
H
Uchida
Y
Y
Nakamura
H
H
Endo
N
N
Asai
T
T
Yoshida
S
S
D000328:Adult; D001323:Autoantibodies / Q000097:blood; D001792:Blood Platelets / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008533:Megakaryocytes; D008875:Middle Aged; D010976:Platelet Count; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood / Q000276:immunology / Q000628:therapy*; D011994:Recombinant Proteins
D001323:Autoantibodies; D007074:Immunoglobulin G; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins