48-Week Study Of GW433908 And Ritonavir Or GW433908 Alone, Twice Daily In Pediatric Patients With HIV Infection

Prior history of having received APV or FPV for \>7 days.

NNRTI use within 14 days prior to study drug administration or anticipated need for concurrent NNRTI therapy during the treatment period of the study.

Subjects who, in the investigator's opinion, are not able to comply with the requirements of the study.

Subject is in the initial acute phase of a Centers for Disease Control and Prevention (CDC) Clinical Category C event or infection (per 1994 classification) at Baseline. Subject may be enrolled provided they are receiving treatment for the infection, such treatment not being contraindicated with FPV, and the subjects are clinically improving at the Baseline visit.

Presence of a malabsorption syndrome or other gastrointestinal dysfunction which might interfere with drug absorption or render the subject unable to take oral medication.

Pregnant or lactating females.

Presence of any serious medical condition (e.g., hemoglobinopathy, chronic anemia, a history of insulin resistance, diabetes, cardiac dysfunction, hepatitis or clinically relevant pancreatitis) which, in the opinion of the investigator, might compromise the safety of the subject.

Grade 3 or 4 transaminase levels (ALT and/or AST) within 28 days prior to study drug administration and/or clinically relevant episodes of hepatitis within the previous 6 months.

Any acute laboratory abnormality at screen which, in the opinion of the investigator, should preclude the subject's participation in the study of an investigational compound. If subjects are found to have an acute Grade 4 laboratory abnormality at screening, this test may be repeated once within the screening window. Any verified Grade 4 laboratory abnormality at screen would exclude a subject from study participation.

Treatment with radiation therapy or cytotoxic chemotherapeutic agents within 28 days of study drug administration or an anticipated need for such treatment within the study period.

Treatment with immunomodulating agents (e.g., systemic corticosteroids, interleukins, interferons) or any agent with known anti-HIV activity (e.g., hydroxyurea or foscarnet) within 28 days of study drug administration.

Treatment with any of the following medications within 28 days prior to receiving study medication or the anticipated need during the study:

Drugs whose plasma concentration may be increased to unsafe levels when co-administered with FPV including:

Amiodarone, astemizole, bepridil, cisapride, dihydroergotamine, ergonovine, ergotamine, flecainide, halofantrine, lidocaine, lovastatin, methylergonovine, midazolam, pimozide, propafenone, quinidine, simvastatin, terfenadine, and triazolam

Drugs with the potential to significantly decrease plasma APV concentrations including:

Carbamazepine, dexamethasone, phenobarbital, primidone, rifampin, St Johns Wort.

Treatment with other investigational drugs/therapies (note: treatments available through a Treatment Investigational New Drug \[IND\] or other expanded-access mechanism will be evaluated on a case-by-case basis in consultation with the sponsor) within 28 days prior to study drug administration or during the treatment period of the study.

History of drug or other allergy which, in the opinion of the investigator, contraindicates participation in the trial or known hypersensitivity to any study medications (e.g., documented hypersensitivity to a nucleoside analogue).

Substantial non-adherence based on history

What this study is about