A Study of Several Anti-HIV Drug Combinations in HIV-Infected Patients Who Have Used Indinavir

To compare the proportion of patients whose plasma HIV-1 RNA is below 500 copies/ml after 16 weeks of treatment. To assess the safety, toxicity, and tolerance of each treatment arm.

While indinavir is currently the most commonly prescribed protease inhibitor, the optimal therapy for a person on an indinavir-containing regimen who experiences a rebound in viral load or never experiences a decrease in viral load below 500 copies per milliliter is unknown. Current clinical practice for such patients typically involves empiric use of a combination of other protease inhibitors (saquinavir/nelfinavir or saquinavir/ritonavir) and at least 1 other antiretroviral agent to which the patient has had little or no prior exposure. This may involve the use of 1 or more reverse transcriptase inhibitors (RTIs) or nonnucleoside reverse transcriptase inhibitors (NNRTIs). This study attempts to formally evaluate some of these options in indinavir-experienced patients.

While indinavir is currently the most commonly prescribed protease inhibitor, the optimal therapy for a person on an indinavir-containing regimen who experiences a rebound in viral load or never experiences a decrease in viral load below 500 copies per milliliter is unknown. Current clinical practice for such patients typically involves empiric use of a combination of other protease inhibitors (saquinavir/nelfinavir or saquinavir/ritonavir) and at least 1 other antiretroviral agent to which the patient has had little or no prior exposure. This may involve the use of 1 or more reverse transcriptase inhibitors (RTIs) or nonnucleoside reverse transcriptase inhibitors (NNRTIs). This study attempts to formally evaluate some of these options in indinavir-experienced patients.

Patients are stratified by HIV RNA (2,000 - 20,000 copies/ml versus 20,000 - 200,000 copies/ml), and randomized to 1 of 6 treatment arms as follows:

Arm A: Saquinavir (SQV) plus ritonavir (RTV) plus delavirdine (DLV) plus adefovir dipivoxil placebo.

Arm B: SQV plus RTV plus DLV placebo plus adefovir dipivoxil. Arm C: SQV plus RTV plus DLV plus adefovir dipivoxil. Arm D: SQV plus nelfinavir (NFV) plus DLV plus adefovir dipivoxil placebo. Arm E: SQV plus NFV plus DLV placebo plus adefovir dipivoxil. Arm F: SQV plus NFV plus DLV plus adefovir dipivoxil. In addition to assigned study treatment patients receive an L-carnitine supplement.

Therapy is administered for 24 weeks. Patients who have an average HIV RNA value for Weeks 12 and 16 that is less than 5,000 copies or a least 1 log below their baseline value may continue their assigned study treatment for an additional 24 weeks. \[AS PER AMENDMENT 3/30/98: Subjects with plasma HIV RNA greater than 5,000 copies/ml may elect to continue or discontinue study medications in the treatment extension and seek the best available treatment.\] \[AS PER AMENDMENT 06/11/98: The dose of adefovir dipivoxil is reduced at or after Week 16. Alternatively, patients may discontinue adefovir dipivoxil/placebo and substitute appropriate antiretroviral agent(s) or add appropriate antiretroviral agent(s) to their reduced-dose regimen. Also, at the discretion of the protocol chairperson, patients who have been on study for more than 16 weeks may substitute appropriate FDA-approved antiretroviral agent(s) for any study medication that must be discontinued because of toxicity. Addition of nonnucleoside reverse transcriptase inhibitors, protease inhibitors, or investigational agents is specifically excluded.\]

Eligibility Criteria:
Inclusion Criteria

Concurrent Medication:

Required:

* Chemoprophylaxis for Pneumocystis carinii pneumonia for all patients who have a CD4 cell count of equal or less than 200 cells/mm3.

Allowed:

* Topical and oral antifungal agents except ketoconazole and itraconazole.
* Treatment, maintenance or chemoprophylaxis with approved agents for opportunistic infections.
* Antibiotics.
* Systemic corticosteroids for 21 days or less for acute problems.
* Recombinant erythropoietin (rEPO) and granulocyte-colony stimulating factor (G-CSF, filgrastim).
* Regularly prescribed medications such as antipyretics, analgesics, allergy medications, antidepressants, sleep medications, oral contraceptives (not as a sole form of birth control), megestrol acetate, or testosterone.
* Alternative therapies, such as vitamins, acupuncture, and visualization techniques.
* \[AS PER AMENDMENT 3/30/98: Calcium channel blockers may be used only with caution.\]

Patients must have:

* HIV-1 infection documented by a licensed ELISA and confirmed by Western blot, HIV culture, HIV antigen, plasma HIV RNA, or a second antibody test other than ELISA.
* 2,000 to 200,000 HIV-1 RNA copies/ml as measured by any Roche-certified laboratory \[AS

PER AMENDMENT 3/30/98:

* using the Roche Amplicor HIV-1 Monitor\] within 30 days of study entry.
* Signed, informed consent from parent or legal guardian for patients less than 18 years of age.

Prior Medication: Required:

* More than 6 months cumulative indinavir therapy.
* Stable indinavir-containing antiretroviral regimen for at least 4 weeks \[2 weeks AS PER AMENDMENT 3/30/98\] prior to study entry.

Exclusion Criteria

Co-existing Condition:

Patients with the following conditions or symptoms are excluded:

* Any active infection requiring acute treatment within 30 days \[21 days AS PER AMENDMENT 3/30/98\] prior to study entry.
* Unexplained temperature greater than 38.5 degrees for any 7 consecutive days within 30 days prior to study entry.
* Malignancy, including Kaposi's sarcoma, that requires systemic chemotherapy.

Concurrent Medication:

Excluded:

* Non-protocol-specified immunomodulatory and/or antiretroviral agents.
* Systemic cytotoxic chemotherapy.
* Ketoconazole, itraconazole, rifampin, rifabutin, alprazolam, amiodarone, astemizole, bepridil, bupropion, cisapride, clorazepate, clozapine, diazepam, encainide, estazolam, flecainide, flurazepam, isotretinoin, meperidine, midazolam, piroxicam, propafenone, propoxyphene, quinidine, terfenadine, triazolam, zolpidem, phenytoin, phenobarbital, carbamazepine, and ergot alkaloids and \[ AS PER AMENDMENT 3/30/98: dexamethasone, ergot derivatives, and pimozide\].

Avoided:

* Herbal medications.

Prior Medication:

Excluded:

* At least 2 weeks or more total ritonavir and/or saquinavir (hard gelatin capsule).
* NNRTIs (nevirapine, delavirdine, DMP-266, etc.), saquinavir (soft gelatin capsule), nelfinavir, 141W94VX-478, and adefovir dipivoxil.
* Immunomodulator \[systemic immunomodulator AS PER AMENDMENT 3/30/98\] or investigational drug therapy within 30 days prior to entry.
* Active immunization within 30 days \[21 days AS PER AMENDMENT 3/30/98\] prior to entry.