To determine the safety and tolerance of alvircept sudotox (sCD4-PE40) given at various dosing intervals and concentrations. To determine whether frequent dosing alters immunogenicity or toxicity. To obtain preliminary data to ascertain whether sCD4-PE40 has activity against HIV in human subjects. To determine whether there is any additive toxicity with combined use of sCD4-PE40 and zidovudine (AZT).