Continuous low-dose interferon-alpha therapy for HIV-related immune thrombocytopenic purpura.
Our objective was to examine the efficacy and toxicity of continuous, low-dose interferon-alpha therapy for human immunodeficiency virus-related immune thrombocytopenic purpura (HIV-ITP) in a Phase II clinical trial overseen by a community-based consortium of physicians conducting clinical trials in HIV-related diseases. Sixteen patients with HIV-ITP defined by prospective clinical criteria were enrolled; the majority had failed other therapies for HIV-ITP. Baseline and serial measurements were made of platelet counts, complete blood counts, serum chemistries, platelet-associated immunoglobulin, and CD4+ T-lymphocyte counts; subjective symptoms and bleeding were recorded. Three million units of interferon-alpha 2b were self-administered by subcutaneous injection every Monday, Wednesday, and Friday for 16 weeks. Thirteen participants were evaluable for response. One obtained a complete response, eight had partial responses, and four had no response to interferon-alpha therapy. The mean absolute platelet count of the group rose from 15.5 x 10(9)/L at baseline to 47.3 x 10(9)/L at 2 weeks and remained in this range for the duration of the study. CD4+ T-lymphocyte counts and serum chemistries did not change significantly during therapy. Ability to detect platelet-associated immunoglobulin did not change in a predictable manner in relation to platelet count response. Hematologic toxicity was limited to one episode of granulocytopenia, which resolved after a lowering of zidovudine dosage. Subjective toxicities were mild and tolerable, and minor bleeding problems improved in all participants so affected. Low-dose, continuous therapy with interferon-alpha resulted in meaningful increases in the platelet counts of the majority of study participants with HIV-ITP. Interferon-alpha was safe and tolerable for most participants with HIV-ITP at the dosage and schedule employed in this study. Interferon-alpha for clinically significant thrombocytopenia and who have failed to respond to zidovudine.
Department of Medicine, University of California, San Francisco 94143-1270, USA.
D W
DW
Northfelt
E D
ED
Charlebois
M I
MI
Mirda
C
C
Child
L D
LD
Kaplan
D I
DI
Abrams
D000328:Adult; D000998:Antiviral Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000276:immunology; D015497:HIV-1; D006801:Humans; D007279:Injections, Subcutaneous; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D010976:Platelet Count; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000209:etiology / Q000628:therapy*; D011994:Recombinant Proteins; D012646:Self Administration
D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins