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Hamill MM, Pettifor JM, Ward KA, Norris SA, Prentice A. Changes in Bone Mineral Density, Body Composition, Vitamin D Status, and Mineral Metabolism in Urban HIV-Positive South African Women Over 12 Months. J Bone Miner Res 2017; 32:1615-1624. [PMID: 28370356 PMCID: PMC5753880 DOI: 10.1002/jbmr.3147] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 03/07/2017] [Accepted: 03/30/2017] [Indexed: 11/07/2022]
Abstract
Human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) are associated with bone loss and poor vitamin D status in white populations, though their relative roles are not known. No previous studies have examined longitudinal changes in areal bone mineral density (aBMD), measured by dual-energy X-ray absorptiometry (DXA), or in vitamin D status in HIV-positive African women. Of 247 premenopausal, urban, black African women from Soweto, South Africa, initially recruited, 187 underwent anthropometry, DXA scanning and blood and urine collections at both baseline and 12 months. Of these, 67 were HIV-negative throughout (Nref), 60 were HIV-positive with preserved CD4 counts at baseline (Ppres), and 60 were HIV-positive with low CD4 counts at baseline, eligible for ART by South African standards of care at the time (Plow). No participant had been exposed to ART at baseline. By 12 months, 51 Plow women had initiated ART, >85% of whom took combined tenofovir disoproxil fumarate (TDF), lamivudine, and efavirenz. By 12 months, Plow and Nref, but not Ppres, increased in body weight and fat mass (group-by-timepoint p ≤ 0.001, p = 0.002, respectively). Plow had significant decreases in aBMD of 2% to 3%, before and after size adjustment, at the femoral neck (p ≤ 0.002) and lumbar spine (p ≤ 0.001), despite significant weight gain. These decreases were associated with increased bone turnover but there were no significant differences or changes over time in vitamin D status, serum phosphate concentrations, or renal phosphate handling. Excluding data from nine Plow women unexposed to ART and 11 Ppres women who had initiated ART accentuated these findings, suggesting the bone loss in Plow was related to ART exposure. This is the first study describing DXA-defined bone loss in HIV-positive Sub-Saharan African women in association with ART. Further work is required to establish if bone loss continues with ongoing ART and, if so, whether this results in increased fracture rates. © 2017 American Society for Bone and Mineral Research.
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Affiliation(s)
- Matthew M Hamill
- Medical Research Council Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, UK.,South African Medical Research Council (SAMRC)/University of Witswatersrand Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of Witswatersrand, Johannesburg, South Africa
| | - John M Pettifor
- South African Medical Research Council (SAMRC)/University of Witswatersrand Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of Witswatersrand, Johannesburg, South Africa
| | - Kate A Ward
- Medical Research Council Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, UK
| | - Shane A Norris
- South African Medical Research Council (SAMRC)/University of Witswatersrand Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of Witswatersrand, Johannesburg, South Africa
| | - Ann Prentice
- Medical Research Council Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, UK.,South African Medical Research Council (SAMRC)/University of Witswatersrand Developmental Pathways for Health Research Unit, Faculty of Health Sciences, University of Witswatersrand, Johannesburg, South Africa
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Schlesinger E, Johengen D, Luecke E, Rothrock G, McGowan I, van der Straten A, Desai T. A Tunable, Biodegradable, Thin-Film Polymer Device as a Long-Acting Implant Delivering Tenofovir Alafenamide Fumarate for HIV Pre-exposure Prophylaxis. Pharm Res 2016; 33:1649-56. [PMID: 26975357 DOI: 10.1007/s11095-016-1904-6] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 03/07/2016] [Indexed: 11/29/2022]
Abstract
PURPOSE The effectiveness of Tenofovir based HIV pre-exposure prophylaxis (PrEP) is proven, but hinges on correct and consistent use. User compliance and therapeutic effectiveness can be improved by long acting drug delivery systems. Here we describe a thin-film polymer device (TFPD) as a biodegradable subcutaneous implant for PrEP. METHODS A thin-film polycaprolactone (PCL) membrane controls drug release from a reservoir. To achieve membrane controlled release, TAF requires a formulation excipient such as PEG300 to increase the dissolution rate and reservoir solubility. Short-term In vitro release studies are used to develop an empirical design model, which is applied to the production of in vitro prototype devices demonstrating up to 90-days of linear release and TAF chemical stability. RESULTS The size and shape of the TFPD are tunable, achieving release rates ranging from 0.5 to 4.4 mg/day in devices no larger than a contraceptive implant. Based on published data for oral TAF, subcutaneous constant-rate release for HIV PrEP is estimated at <2.8 mg/day. Prototype devices demonstrated linear release at 1.2 mg/day for up to 90 days and at 2.2 mg/day for up to 60 days. CONCLUSIONS We present a biodegradable TFPD for subcutaneous delivery of TAF for HIV PrEP. The size, shape and release rate of the device are tunable over a >8-fold range.
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Affiliation(s)
- Erica Schlesinger
- UC Berkeley-UCSF Graduate Program in Bioengineering, 1700 4th Street Room 204, UCSF Mission Bay Campus,, San Francisco, California, 94158, USA
| | - Daniel Johengen
- Department of Bioengineering and Therapeutic Sciences, 1700 4th Street Room 204, UCSF Mission Bay Campus,, San Francisco, California, 94158, USA
| | - Ellen Luecke
- Women's Global Health Imperative, RTI International, 351 California Street,, San Francisco, California, 94104, USA
| | - Ginger Rothrock
- Emerging Technologies, Research Triangle Institute (RTI) International, Research Triangle Park, North Carolina, 27709, USA
| | - Ian McGowan
- University of Pittsburgh Medical School, 204 Craft Ave Rm B-621, Pittsburgh, Pennsylvania, 15213, USA
| | - Ariane van der Straten
- Women's Global Health Imperative, RTI International, 351 California Street,, San Francisco, California, 94104, USA.,Center for AIDS Prevention Studies (CAPS), Department of Medicine, UCSF Mission Bay Campus,, San Francisco, California, 94158, USA
| | - Tejal Desai
- UC Berkeley-UCSF Graduate Program in Bioengineering, 1700 4th Street Room 204, UCSF Mission Bay Campus,, San Francisco, California, 94158, USA. .,Department of Bioengineering and Therapeutic Sciences, 1700 4th Street Room 204, UCSF Mission Bay Campus,, San Francisco, California, 94158, USA.
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