Participants in this study will receive lamivudine (3TC), stavudine (d4T), abacavir (ABC), amprenavir (APV), and ritonavir (RTV) for at least 52 weeks. During this induction phase, participants will be followed through regular study visits every 4 or 8 weeks. If the participant's viral load and CD4 counts are within study parameters at the end of 52 weeks, the participant will discontinue all antiretroviral medications simultaneously. Participants in the treatment interruption phase will be followed weekly initially, every 2 weeks for 8 weeks, and then every 4 or 8 weeks. Treatment may be restarted if necessary during this phase based on viral load and CD4 counts. If treatment is restarted, the participant will receive 3TC, d4T, APV, and RTV but not ABC. During this reinduction phase, participants will be followed every 4 or 8 weeks.