SUN-720 X linked hypophosphatemia XLH Follow up experience in Argentina

Abstract Disclosure: E. Giacoia: Ultragenyx. A.C. Cantó: Ultragenyx. M.C. Balonga: Ultragenyx. Introduction: XLH is a rare, chronic, disabling genetic bone disease characterized by renal phosphate loss and hypophosphatemia secondary to an increase in plasma fibroblast factor 23 (FGF23). As treatments, conventional therapy with phosphorus salts, calcitriol and vitamin D and the monoclonal antibody against FGF23, burosumab, are described. Objective: To analyze the follow-up of patients with XLH under conventional treatment vs burosumab Materials and methods: Descriptive and analytical study. 10 patients diagnosed with XLH were analyzed and evaluated from January to December 2024 characteristics of age, gender, body mass index (BMI), phosphataemia, calcemia, parathormone (PTH), alkaline phosphatase (ALP), type of inheritance (familial or sporadic) and occupation in patients treated with conventional therapy. vs burosumab in 10 patients Results: p class="MsoNormal"> Conclusions: At one year of follow-up, patients under treatment with burosumab presented better levels of phosphataemia, FAL and PTH and all were in stable work. 4/6 patients under conventional treatment are unemployed. Longer-term studies are needed to evaluate the impact of both therapies. Weber T. et al Long-term Burosumab Administration Is Safe and Effective in Adults With X-linked Hypophosphatemia. JCEM, 2023, 108, 155-165. Giacoia E. et al. Characterization of adult patients with X-linked hypophosphatemia at a specialized center in Buenos Aires, Argentina.Arch Endocrinol Metab, 2024, v.68, 1-5, e240023. Presentation: Sunday, July 13, 2025