Thank you for your post.
If your patient is doing well (as he appears to be), I'd see no reason to discontinue his current medications. While most US treaters use atazanavir (Reyataz) with ritonavir boosting, there are a number of patients who in my clinic (and others) who are doing quite well on the very Epzicom/atazanavir regimen that you describe.
The real core to your question is why is the patient or you considering a treatment change or interruption. The later has been well discussed here and on our sister site, TheBody.com- treatment interruptions, with the exception of stopping for treatment failure or toxicity, is generally not recommended because of increased risk of HIV- and non-HIV complications.
Should ulimately, your patient stop current treatment and if his viral load is undetectable at the time to discontinuation, there should be little risk of the development of drug resistance, hence he is little risk in resuming the same treatment in the future.
Hope this helps. BY
