To evaluate the pharmacokinetics (PK) of LPV/r with saquinavir in HIV-1 infected children. To evaluate treatment response (clinical, immunological and virological) to LPV/r, SQV in Thai children.

The PK and 24 week data has been published in Pediatric Infectious Diseases Journal. It showed that plasma drug concentrations of saquinavir, lopinavir and ritonavir were at the higher limits of expected ranges for adult treatment at approved dosages (1000/100 mg BID for saquinavir, 400/100 mg BID for lopinavir/r). The regimen was well tolerated and showed significant CD4 rise and VL decline at 48 weeks.

Inclusion Criteria:

1. Confirmed HIV-1 infection by HIV-DNA PCR if < 18 months old or by HIV ELISA if greater than or equal to 18 months old
2. Subject is less than or equal to 16 years of age at the day of the first dosing.
3. Subject is failing a current NRTI and/or NNRTI containing regimen and is naïve to protease inhibitor containing therapy.
4. Results of biochemistry and haematology testing should be within pre-specified ranges.
5. Subject is able to swallow capsules
6. Caretaker(s) is/are able and willing to sign the Informed Consent Form prior to screening evaluations.

Exclusion Criteria:

1. History of sensitivity/idiosyncrasy to lopinavir, ritonavir, saquinavir or chemically related compounds or excipients which may be employed in the trial.

2. Relevant history or current condition that might interfere with drug absorption, distribution, metabolism or excretion.

3. Inability of both child and caregiver(s) to understand the nature and extent of the trial and the procedures required.

4. Use of any of concomitant medication, including the drug listed below, that may interfere with the pharmacokinetics of LPV/r or SQV.

   • NNRTIs
   • Rifampicin
   • Rifabutin
   • Phenobarbital
   • Phenytoine
   • Carbamazepine
   • Dexamethasone
   • Ketoconazole
   • Clarithromycin

5. Pregnancy