Simplification From Tenofovir Plus Lamivudine or Emtricitabine Plus Ritonavir-Boosted-Protease Inhibitor to Ritonavir-Boosted-Atazanavir Plus Lamivudine in Virologically-Suppressed-HIVInfected Adults With Osteopenia

Inclusion criteria

• Human immunodeficiency virus-1-infected subjects with age ≥18 years old
• Hip or spine T-scores between < -1.0 and >-2.5 by dual-energy X-ray absorptiometry (in the previous 24 weeks)
• Stable antiretroviral treatment based on tenofovir and lamivudine or emtricitabine and boosted protease inhibitor for at least 24 weeks.
• Having plasma human immunodeficiency virus-1 RNA <50 copies/mL for at least the previous 24 weeks, including at least two samples.

Exclusion criteria

• Pregnancy, breast-feeding status or plans for pregnancy in the short term
• Primary genotypic resistance mutations and/or previous virological failures to atazanavir or lamivudine/emtricitabine
• Chronic hepatitis B infection
• Patients with indication for therapy for the prevention of bone fractures
• 25-OH vitamin D deficiency (< 10ng/mL)
• Hypogonadism (low total testosterone according to local reference range)
• Hypothyroidism (low T4 and increased thyroid stimulating hormone levels according to local reference ranges)
• Hyperparathyroidism (increased parathyroid hormone level with hypercalcaemia according to local reference ranges)
• Having received oral corticosteroids or inhaled fluticasone (daily doses higher than 5 mg/d prednisone equivalent for 3 months or more)
• Using anti-resorptive therapy (Calcium and vitamin D supplements are encouraged but not mandated)
• Body mass index lower than 19