The purpose of this study is to study the pharmacokinetics profiles of generic lopinavir/ritonavir and Pediatric Aluvia® at reduced dose by assessing safety, tolerability and efficacy.

This is a prospective, 2 arms, randomized intensive PK study with cross over design. This design will provide us optimal information to answer our research question. First and most important, we can assess the PK when lopinavir/r is used in a dose reduced form. By randomizing the patients to either Abbott's pediatric Aluvia dose reduction or India generic LPV/r dose reduction will allow us to assess the differences in AE severity and frequency. Using the standard abbott product as a control our study will provide important information about the bioavailability of the generic product. Although it's not an original BE design we must be able to make preliminary comparisons.

Inclusion Criteria:

1. Signed informed consent
2. Evidence of HIV infection (confirmed positive ELISA and/or documented history of measurable HIV RNA)
3. Age> 18 years
4. Have been on standard dose of any PI containing regimen for at least 4 weeks prior to study entry
5. Currently having no AIDS defining illness
6. Plasma HIV RNA < 50 copies/mL for at least 24 weeks
7. Willing to adhere to the protocol requirements

Exclusion Criteria:

1. Any history of taking CYP450 inhibitors or inducers, or any gastric acid-reducing drugs within 14 days of enrollment in the study
2. Current pregnancy or lactating
3. Active opportunistic infection
4. ALT/ AST more than 2x upper limit
5. creatinine more than 1.5 time the upper limit
6. Relevant history or current condition, illness that might interfere with drug absorption, distribution, metabolism or excretion
7. History of sensitivity/idiosyncrasy to the drug or chemically related compounds or pharmaceutical excipients which may be employed in the study.
8. Active drug abuse