<qa>  What is a prior AIDS defining event acceptable?12. Willingness to abstain from ingesting substances which may alter plasma study drug levels by interaction with the cytochrome P450 system 13. A prior AIDS defining event, excluding mycobacterial and invasive fungal infections, is acceptable as long as it has resolved or the subject has been on stable treatment e.g. opportunistic infection for at least 12 weeks before screening Visit 1. Note that prior oral thrush, candida esophagitis and cutaneous candida is acceptable. 