Study Objective: To determine the effect of zidovudine on platelet counts in patients with human immunodeficiency virus (HIV)-associated thrombocytopenia.
Design: The study was prospective, controlled, and blinded. Each patient received active drug and placebo. Platelet counts were compared before and after receiving zidovudine.
Setting: Outpatient clinics in Geneva, Lausanne, and Zürich, Switzerland.
Patients: Sequential sample of ten patients (five intravenous drug addicts, four homosexual men, one Zairian) who were seropositive for HIV, and had platelet counts between 20 and 100 × 109/L (20 000 to 100 000/mm3). Patients with the acquired immunodeficiency syndrome (AIDS) were not enrolled. None had been previously treated for thrombocytopenia, and no medication except zidovudine or placebo was administered during the trial period.
Interventions: Five patients received 8 weeks of zidovudine (2 g/d for 2 weeks, and 1 g/d for 6 weeks), followed by 8 weeks of placebo. The other five patients received placebo for 8 weeks followed by zidovudine.
Measurements and Main Results: Platelet counts increased in each patient while on zidovudine, but not while on placebo; the mean increase was 54.6 × 109/L ± 11.25 (SE) from 53.2 to 107.8 × 109/L (P < 0.004). After the end of zidovudine treatment, platelet counts remained elevated for more than 4 weeks in three of five patients. One patient developed granulocytopenia and anemia during treatment with zidovudine.
Conclusions: Zidovudine is a potential new treatment for HIV-associated thrombocytopenia.