8387 PTH Analogs in the Management of Osteoporosis in Patients with HIV: An Under-Investigated Treatment Option

Abstract Disclosure: K. Cappetta: None. F. Erenler: None. Background: Several studies evaluating the fracture risk in individuals with HIV suggest that their fracture burden is elevated compared to the general population due to a multitude of factors.[1] For example, highly active antiretroviral therapy (HAART) is associated with decreased bone mineral density (BMD).[1] Certain agents such as tenofovir disoproxil fumarate (TDF) are particularly associated with reduced BMD, whereas tenofovir alafenamide (TAF) tends to cause fewer deleterious effects.[1] Bisphosphonates are considered first-line options for the treatment of osteoporosis in HIV-infected adults.[1] PTH analogs such as abaloparatide are not well-studied in this population, but case reports with teriparatide have shown promising results.2 To the best of our knowledge, we present the first case in which abaloparatide was initiated in a patient with osteoporosis and HIV with subsequent significant BMD gains. Case: A 64 year-old Indian woman with well-controlled HIV (CD4+ cell count 370 cells/µL; undetectable viral load) on HAART and no history of fractures or hypercalciuria was diagnosed with osteoporosis in 2013 by dual-energy X-ray absorptiometry (DXA) scan. Her most significant risk factors are postmenopausal state, HIV, and HAART, including TDF until 2015; in 2015, she was transitioned to a combination therapy that includes TAF. She was treated with alendronate weekly from 2013-2018. DXA in Sept. 2021 showed T-scores of -2.7 (BMD 0.738 g/cm2) at the spine, -2.3 (0.592 g/cm2) at the femoral neck, and -1.7 (0.732 g/cm2) at the total hip. Given her history of prolonged bisphosphonate exposure, young age, and worst T-score at the spine, the decision was made to start the patient on anabolic therapy with abaloparatide in July 2022. Repeat DXA in Aug. 2023 showed T-scores of -2.4 (0.777 g/cm2) at the spine (a statistically significant 5.3% gain in BMD vs. 2021), -2.4 (0.583 g/cm2) at the femoral neck, and -1.7 (0.733 g/cm2) at the total hip (stable BMD). Discussion: Bone microarchitecture, especially trabecular bone (such as is found at the spine), and the balance of bone resorption and formation is negatively altered by the host immune response and viral proteins in HIV-infected adults, leading to a high prevalence of osteopenia and osteoporosis in this population.[1] Abaloparatide increases BMD—preferentially at the spine—by stimulating osteoblast function.2 Although data on these agents in individuals with HIV are limited, PTH analogs can be efficacious in the treatment of osteoporosis in this population, especially for low BMD at the spine, and warrants further investigation. References: 1.Ahmed M, et al. Bone Health in People Living with HIV/AIDS: An Update of Where We Are and Potential Future Strategies. Microorganisms. 2023; 11(3):789. 2.Wheeler AL, et al. Teriparatide treatment of osteoporosis in an HIV-infected man: a case report and literature review. AIDS. 2015 Jan 14;29(2):245-6. Presentation: 6/3/2024