{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T12:16:11Z","timestamp":1779279371488,"version":"3.51.4"},"reference-count":20,"publisher":"The Endocrine Society","issue":"6","license":[{"start":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T00:00:00Z","timestamp":1778025600000},"content-version":"vor","delay-in-days":7,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Clementia\/Ipsen"},{"DOI":"10.13039\/100017655","name":"Incyte","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100017655","id-type":"DOI","asserted-by":"publisher"}]},{"name":"AshiBio"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,29]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>McCune-Albright syndrome (MAS) is a rare disorder characterized by fibrous dysplasia (FD), caf\u00e9-au-lait spots, and hyperfunctioning endocrinopathies. FD lesions can overproduce fibroblast growth factor-23 (FGF-23), leading to renal phosphate wasting, hypophosphatemia, and impaired bone mineralization. Conventional treatment with oral phosphate and calcitriol is limited by gastrointestinal intolerance. Burosumab, a monoclonal antibody against FGF-23, is approved for X-linked hypophosphatemia and tumor-induced osteomalacia and has shown promise in case reports of pediatric and adult patients with MAS-related FGF-23-mediated hypophosphatemia. We describe a 46-year-old woman with MAS and extensive FD who presented with worsening bone pain and FGF-23-mediated hypophosphatemia. She was started on phosphate and calcitriol with improvement in pain. Due to failure to achieve treatment targets, she was transitioned to burosumab 0.50\u2005mg\/kg injections every 4 weeks with normalization of serum phosphorus but persistent elevation of alkaline phosphatase. This case represents the second reported adult and oldest patient treated with burosumab for MAS-related FGF-23-mediated hypophosphatemia after failure of conventional therapy. Although its use in MAS remains off-label, burosumab may provide a more targeted and better-tolerated therapeutic option.<\/jats:p>","DOI":"10.1210\/jcemcr\/luag086","type":"journal-article","created":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T12:48:42Z","timestamp":1773838122000},"source":"Crossref","is-referenced-by-count":0,"title":["Burosumab use in fibroblast growth factor-23-mediated hypophosphatemia in McCune-Albright syndrome\/fibrous dysplasia"],"prefix":"10.1210","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-2391-115X","authenticated-orcid":false,"given":"Marah","family":"Alsayed Hasan","sequence":"first","affiliation":[{"name":"Division of Endocrinology, Diabetes and Metabolism, Hospital of the University of Pennsylvania , Philadelphia, PA 19104 ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7138-596X","authenticated-orcid":false,"given":"Mona","family":"Al Mukaddam","sequence":"additional","affiliation":[{"name":"Division of Endocrinology, Diabetes and Metabolism, Hospital of the University of Pennsylvania , Philadelphia, PA 19104 ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"80","published-online":{"date-parts":[[2026,5,6]]},"reference":[{"issue":"1","key":"2026052007563799200_luag086-B1","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1186\/s13023-019-1255-6","article-title":"Correction to: best practice management guidelines for fibrous dysplasia\/McCune-Albright syndrome: a consensus statement from the FD\/MAS international consortium","volume":"14","author":"Javaid","year":"2019","journal-title":"Orphanet J Rare Dis"},{"issue":"5","key":"2026052007563799200_luag086-B2","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1007\/s11914-016-0317-0","article-title":"Fibrous dysplasia\/McCune-Albright syndrome: clinical and translational 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