- In the opinion of the investigator, the best treatment regimen for the subject must be an optimized ART regimen consisting of >=3 drugs, the optimized regimen must contain at least 2 active drugs, one of which must be a ritonavir-boosted PI (>=100 mg ritonavir). With the exception of etravirine, NNRTIs may not be a component of the optimized regimen.