Interferon-alpha is effective in the treatment of HIV-1-related, severe, zidovudine-resistant thrombocytopenia. A prospective, placebo-controlled, double-blind trial.
OBJECTIVE
To determine the effect of interferon-alpha for severe, zidovudine-resistant, HIV-1-related thrombocytopenia.


METHODS
Prospective, randomized, double-blind, placebo-controlled, multicenter, crossover trial.


METHODS
Outpatient clinics in Central Northern Italy.


METHODS
15 sequential patients positive for HIV-1 with platelet counts less than 25 x 10(9)/L who were refractory to 1 month of full-dose (1000 mg/d) zidovudine.


METHODS
Interferon-alpha (3 million units) or placebo (1 mL saline) three times a week subcutaneously for 4 weeks, followed by a 4-week washout period. Patients were then switched to the alternative treatment for the next 4 weeks, followed by another 4 weeks of washout, and they were randomly assigned to either sequence of treatment. Patients received zidovudine (200 mg three times daily) throughout the study.


METHODS
The primary end point was the platelet count (measured weekly). Secondary end points were qualitative assessment of the platelet response; bleeding time; p24 antigen in serum; CD4/CD8 counts; beta 2-microglobulin in serum; and platelet-associated IgG.


RESULTS
Interferon-alpha significantly increased platelet counts in the 12 patients who completed the study (baseline level, 15.6 +/- 7.1 x 10(9)/L; after 4 weeks of interferon-alpha therapy, 82.2 +/- 52.2 x 10(9)/L). The estimated increase in the platelet count after interferon-alpha compared with placebo was 60.0 x 10(9)/L (95% CI, 23.2 to 96.8 x 10(9)/L). The increase was already statistically significant after 3 weeks (66.6 +/- 49.7 x 10(9)/L) and remained significantly increased 1 week after discontinuing interferon-alpha therapy (58.2 +/- 45.0 x 10(9)/L). Placebo did not modify the platelet count. The bleeding time was significantly shortened by interferon-alpha. Four of 12 patients who had more serious alterations of some measures reflecting disease severity did not respond to interferon-alpha. No relevant side effects were observed.


CONCLUSIONS
Interferon-alpha is a safe and effective treatment for zidovudine-resistant, HIV-related thrombocytopenia.
Marroni
M
M
University of Perugia, Italy.
Gresele
P
P
Landonio
G
G
Lazzarin
A
A
Coen
M
M
Vezza
R
R
Sinnone
M S
MS
Boschetti
E
E
Nosari
A M
AM
Stagni
G
G
Nenci
G G
GG
Pauluzzi
S
S
D000163:Acquired Immunodeficiency Syndrome / Q000150:complications*; D000328:Adult; D001760:Bleeding Time; D004311:Double-Blind Method; D005260:Female; D015497:HIV-1; D006801:Humans; D016898:Interferon-alpha / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D010976:Platelet Count; D011446:Prospective Studies; D013921:Thrombocytopenia / Q000097:blood / Q000209:etiology / Q000628:therapy*; D015215:Zidovudine / Q000627:therapeutic use
D016898:Interferon-alpha; D015215:Zidovudine