- zidovudine (ZDV) + lamivudine (3TC), ZDV + didanosine (ddI), stavudine (d4T) + 3TC, or d4T + ddI. [AS PER AMENDMENT 10/31/97: A nucleoside analogue is considered "new" if it was never taken previously or if prior exposure to the nucleoside analogue was for less than 30 days and occurred more than 3 months prior to entry, with the exception of 3TC. For 3TC exposure to be considered "new", prior exposure must have been less than 1 week and must have occurred more than 3 months prior to entry.]