The Safety and Effectiveness of Three Anti-HIV Drug Combinations in HIV-Infected Patients Who Have Taken AZT

A Randomized Lamivudine (3TC)/Dideoxycytidine (ddC) Double-Blind Multicenter Trial (With Open-Label AZT) to Evaluate the Safety and Efficacy of Low Dose 3TC Administered Concurrently With AZT Versus High Dose 3TC Administered Concurrently With AZT Versus ddC Administered Concurrently With AZT in the Treatment of HIV-1 Infected, AZT-Experienced (>= 24 Weeks) Patients With CD4 Counts of 100-300 Cells/mm3

To evaluate the safety and efficacy of low and high doses of lamivudine ( 3TC ) in combination with zidovudine ( AZT ) and zalcitabine ( dideoxycytidine; ddC ) in combination with AZT.

PER 02/27/95 AMENDMENT: To evaluate the efficacy and safety of both blinded and open-label combination therapy.

Patients are randomized to one of three treatment arms: low-dose 3TC plus AZT, high-dose 3TC plus AZT, or ddC plus AZT. Treatment continues for 32 weeks, with possible extension to 52 weeks.

PER 02/27/95 AMENDMENT: Patients may continue therapy on AZT and low-dose 3TC on an open-label basis. Open-label therapy continues with follow-up every 8 weeks until intolerable toxicity occurs or study terminates.

Inclusion Criteria

Patients must have:

• HIV positivity.
• CD4 count 100-300 cells/mm3.
• Prior AZT therapy for 24 or more weeks and currently on AZT.

Exclusion Criteria

Patients with the following prior conditions are excluded:

• History of intolerance to AZT.
• History of grade 2 or worse peripheral neuropathy.

Prior Medication:

Excluded:

• Any prior antiretroviral therapy other than AZT.

Required:

• Concomitant AZT therapy.

Required:

• At least 24 weeks of prior AZT.