Inclusion Criteria

Concurrent Medication:

• Background AR nucleoside therapy is required, although background AR therapy may also be no background therapy. However, the use of protease inhibitors is not recommended as monotherapy unless there is no other alternative. Therefore, patients who are not on AR treatment may be enrolled at the discretion of the clinician.

Allowed:

• Saquinavir.

Patients must have:

• Documented HIV infection.
• A CD4+ cell count <= 100/mm3 within 3 months prior to the study. [AS PER AMENDMENT 3/11/98: CD4+ cell count <= 200/mm3 any time prior to entry].
• Parental consent if patient is < 18 years old.

Prior Medication:

Allowed:

• Saquinavir (SQV).

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms or conditions are excluded:

• Stage 2 or greater AIDS dementia complex.
• [AS PER AMENDMENT 10/2/97: Any acute disease or condition that would, in the physician's judgement, contraindicate starting NFV or RTV.]
• Known hypersensitivity to RTV or any of its ingredients (for patients assigned to RTV therapy).

Concurrent Medication:

Excluded:

• Concomitant use of protease inhibitors.
• Concomitant treatments that cannot be discontinued, and in the physician's judgement, should not be taken with NFV or RTV.

AS PER AMENDMENT 10/2/97:

• For patients randomized to NFV:
• Concomitant therapy with terfenadine, astemizole, cisapride, triazolam, midazolam, ergot derivatives, amiodarone, quinidine, or rifampin.

For patients randomized to IDV:

• Concomitant therapy with terfenadine, astemizole, cisapride, triazolam, midazolam, and rifampin.

Patients with any of the following prior symptoms are excluded:

AS PER AMENDMENT 10/2/97:

• History of clinically significant hypersensitivity reaction to any component of NFV tablets (for patients assigned to NFV therapy).

Prior Medication:

Excluded:

• Prior use of protease inhibitors except SQV.

[AS PER AMENDMENT 10/2/97:

• Prior use of IDV for more than 4 weeks or other protease inhibitors (except SQV) for any prior duration.]