Bone Loss and Immune Reconstitution in HIV/AIDS (BLIR-HIV)

Summary

With the increasing age of people living with HIV/AIDS, age-induced osteoporosis is likely to be compounded by HIV/AIDS and HAART-associated bone loss. Mechanistically, osteoclasts the cells responsible for bone resorption form under the influence of the key osteoclastogenic cytokine receptor activator of nuclear factor kappa-Β ligand (RANKL). The osteoclastogenic and proresorptive activities of RANKL are moderated by its physiological decoy receptor osteoprotegerin (OPG). Imbalance in the ratio of RANKL to OPG alters osteoclastic bone resorption and lead to osteoporosis. Activated T- and B-cells are a major source of RANKL, while normal physiological B-cells are a major source of OPG. T-cells regulate the production of OPG by B-cells. Thus changes in the immune system induced by HIV/AIDS and/or by HAART could affect B-cell and T-cells RANKL and OPG production. Indeed, data from our group shows that in an animal model of HIV/AIDS, the HIV-1 Transgenic rat, the development of osteoporosis is recapitulated as observed in HIV-infected patients, and B-cell OPG and RANKL production are concurrently down regulated and upregulated respectively. Furthermore, preliminary data in HIV-infected subjects suggests dramatic acute upswing in bone resorption following HAART initiation that peaks at 12 weeks and then declines. Based on these findings, the investigators hypothesize HAART associated bone loss is driven by immune reconstitution. Because this effect of HAART is dramatic in magnitude but short in duration, the investigators propose to apply antiresorptive agent (zoledronic acid, reclast®) to specifically spare patients from this dramatic but acute bone damage.

Timeline

Start

2011-01

Primary completion

2017-04-13

Completion

2017-04-13

Publications

• Background Vikulina T, Fan X, Yamaguchi M, Roser-Page S, Zayzafoon M, Guidot DM, Ofotokun I, Weitzmann MN. Alterations in the immuno-skeletal interface drive bone destruction in HIV-1 transgenic rats. Proc Natl Acad Sci U S A. 2010 Aug 3;107(31):13848-53. doi: 10.1073/pnas.1003020107. Epub 2010 Jul 19.
• Background Ofotokun I, Weitzmann MN. HIV-1 infection and antiretroviral therapies: risk factors for osteoporosis and bone fracture. Curr Opin Endocrinol Diabetes Obes. 2010 Dec;17(6):523-9. doi: 10.1097/MED.0b013e32833f48d6.
• Results Ofotokun I, Titanji K, Lahiri CD, Vunnava A, Foster A, Sanford SE, Sheth AN, Lennox JL, Knezevic A, Ward L, Easley KA, Powers P, Weitzmann MN. A Single-dose Zoledronic Acid Infusion Prevents Antiretroviral Therapy-induced Bone Loss in Treatment-naive HIV-infected Patients: A Phase IIb Trial. Clin Infect Dis. 2016 Sep 1;63(5):663-671. doi: 10.1093/cid/ciw331. Epub 2016 May 18.
• Ofotokun I, Collins LF, Titanji K, Foster A, Moran CA, Sheth AN, Lahiri CD, Lennox JL, Ward L, Easley KA, Weitzmann MN. Antiretroviral Therapy-Induced Bone Loss Is Durably Suppressed by a Single Dose of Zoledronic Acid in Treatment-Naive Persons with Human Immunodeficiency Virus Infection: A Phase IIB Trial. Clin Infect Dis. 2020 Oct 23;71(7):1655-1663. doi: 10.1093/cid/ciz1027.

Drugs

Indications