The investigators propose a proof-of-concept, pathogenesis-oriented, randomized, placebo-controlled pilot study to assess whether the addition of an angiotensin converting enzyme (ACE) inhibitor to standard Highly Active Antiretroviral Therapy (HAART) reverses lymphoid fibrosis, and whether this leads to more effective HIV-specific host immune responses and an accelerated clearance of the latent reservoir.

Inclusion Criteria include:

• Stable HAART with maintenance of plasma HIV RNA levels below level of detection (< 40-75 copies/mL) for ≥ 12 months
• > 90% adherence to HAART within preceding 30 days

Exclusion Criteria include:

• Screening systolic blood pressure < 110mm Hg or diastolic blood pressure < 60mm Hg
• Current use of any ACE inhibitor, angiotensin receptor blocker, or aldosterone antagonist
• Known diabetes mellitus or cardiovascular/kidney/collagen vascular disease
• Pregnant/breastfeeding women.