AS PER AMENDMENT 5/9/96: All AZT monotherapy options have been eliminated. Patients will be randomized to either Arm II or Arm III, regardless of their codon 215 status. All patients who were randomized to Arm I following a mutation at codon 215 will be rerandomized to Arm II or Arm III. All patients who were randomized to either Arm II or Arm III following a mutation at codon 215 will remain on their initial randomized assignment.