Soluble interleukin-2 receptor decrease in the sera of HIV-infected patients treated with zidovudine.

Laboratory parameters which are modified following administration of zidovudine are becoming increasingly useful in monitoring the efficacy of treatment of early stages of HIV-1 infection. The serum levels of soluble interleukin (sILR)-2 receptor, which have been reported to increase early in HIV-1 infection, were found to be significantly lower in 24 patients being treated with zidovudine than in 69 patients who were not treated, 28 of whom had CD4+ counts greater than 400 x 10(6)/l, and 41 less than 400 x 10(6)/l, respectively (P less than 0.0001). A prospective study group of 33 subjects treated with zidovudine demonstrated a decrease in sIL-2R during therapy (base values 2113 +/- 1131 versus 1444 +/- 728 after 90 days of therapy; P less than 0.0007). The reduction of sIL-2R was greater in those subjects were p24 antigen became negative during treatment. sIL-2R therefore seems to be a useful tool in the monitoring of therapy with zidovudine.