Maintenance therapy after quadruple induction therapy in HIV-1 infected individuals: Amsterdam Duration of Antiretroviral Medication (ADAM) study

Abstract

Background: Highly active antiretroviral therapy (HAART) has led to health benefits for patients infected with HIV-1. However, long-term use of multidrug regimens is difficult to sustain. Simplifying antiretroviral treatment regimens would increase patients' adherence and minimise toxicity. We investigated the feasibility of a strategy of induction therapy followed by maintenance therapy with HAART in a randomised open-label study.

Methods: From March, 1997, we enrolled patients infected with HIV-1 with at least 200 CD4 cells/microL, at least 1000 HIV-1 RNA copies/mL in plasma, and no previous exposure to antiretroviral drugs. After 26 weeks of induction therapy (stavudine, lamivudine, saquinavir, and nelfinavir) patients were randomly allocated maintenance therapy (either stavudine and nelfinavir or saquinivir and nelfinavir) or prolonged induction therapy (if the plasma HIV-1 RNA concentration at weeks 24 and 25 was <50 copies/mL).

Findings: In February, 1998, we discontinued randomisation after an interim analysis. 62 patients had been enrolled. 39 (91%) of the 43 patients who were followed up for at least 26 weeks had an undetectable plasma HIV-1 RNA concentration at week 16. At week 26, 31 patients were randomly allocated treatment. Of these patients 25 had a total follow-up of at least 36 weeks. At week 36, a higher proportion of patients on maintenance therapy (nine [64%] of 14) had a detectable HIV-1 RNA than patients on prolonged induction therapy (one [9%] of 11, p=0.01). The initial virion-clearance rate during induction therapy was higher in five patients on maintenance therapy with a sustained undetectable plasma HIV-1 RNA concentration than in nine patients with recurrence of a detectable plasma HIV-1 RNA concentration at week 36 (0.35 vs 0.19 per day, respectively; p=0.0008).

Interpretation: The induction regimen provided a rapid suppression of viral replication to below 50 copies/mL. However, suppression was not sustained in a considerable number of patients who went onto maintenance therapy. It is currently inadvisable to continue attempts at moving from induction to maintenance therapy in day-to-day practice.