AZT has been found to inhibit both the in vitro (in test tube) and cell killing effects of HIV, and both interferons (IFN-A and IFN-A2A) have shown antiviral and antitumor effect in Kaposi's sarcoma. It is reasonable to assume that a synergistic effect and enhanced antitumor response may be seen with combination therapy. A study to evaluate the safety and efficacy of AZT in combination with IFN-A or IFN-A2A is warranted.