Objective: To evaluate clinical efficacy and toxicity of low-dose oral natural human interferon-alpha (nHuIFN alpha) on CD4+ lymphocyte counts and clinical symptoms in patients with HIV-1 infection.
Design: Double-blind, randomized, placebo-controlled trial with crossover.
Setting: Private practice specializing in the treatment of patients with AIDS.
Patients, participants: Only patients with HIV-1 infection and CD4+ lymphocyte counts between 200 and 500 x 10(6)/l were included for study. Thirty out of thirty-one patients at study entry completed treatment with placebo, and 29 completed nHuIFN alpha treatment. Mean patient age was 36 years (range, 25-58 years). The 30 patients included 26 men, of whom 22 were homosexual, and four women; five were drug users and none were currently on zidovudine therapy, although three had been previously.
Interventions: Patients were randomly assigned to cohorts of 10 to receive either 200 IU nHuIFN alpha once daily orally absorbed or placebo with crossover after 6 weeks.
Main outcome measures: Every 2 weeks, a detailed history, physical examination, and laboratory tests, including CD4+ and CD8+ lymphocyte counts, were conducted.
Results: There was only a slight, transient increase in mean CD4+ lymphocyte counts after 4 weeks of treatment with nHuIFN alpha, compared with a slight decline when placebo was administered. This effect reached statistical significance in a subgroup of patients only and was not sustained after 6 weeks. There were no significant changes in weight and clinical symptoms. All patients remained HIV-1-antibody-positive. Treatment-related adverse reactions were not observed.
Conclusions: Our double-blind, randomized, placebo-controlled clinical trial did not confirm a previous report of efficiency of oral nHuIFN alpha. Although non-toxic, our data do not justify the widespread use of low-dose oral nHuIFN alpha in HIV-infected patients outside controlled clinical trials.