Burosumab for the treatment of cutaneous-skeletal hypophosphatemia syndrome

Lillian Abebe; Kim Phung; Marie-Eve Robinson; Richelle Waldner; Sasha Carsen; Kevin Smit; Andrew Tice; Joanna Lazier; Christine Armour; Marika Page; Saunya Dover; Frank Rauch; Khaldoun Koujok; Leanne M Ward

doi:10.1016/j.bonr.2023.101725

Burosumab for the treatment of cutaneous-skeletal hypophosphatemia syndrome

Bone Rep. 2023 Nov 11:20:101725. doi: 10.1016/j.bonr.2023.101725. eCollection 2024 Mar.

Authors

Lillian Abebe¹, Kim Phung^{1

2}, Marie-Eve Robinson^{2

3}, Richelle Waldner⁴, Sasha Carsen^{2

5}, Kevin Smit^{2

5}, Andrew Tice^{2

5}, Joanna Lazier^{6

7}, Christine Armour^{6

7}, Marika Page¹, Saunya Dover¹, Frank Rauch^{8

9}, Khaldoun Koujok^{1

10}, Leanne M Ward^{1

2

3}

Affiliations

¹ The Ottawa Pediatric Bone Health Research Group, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, ON K1H 8L1, Canada.
² Department of Pediatrics, Faculty of Medicine, University of Ottawa, 550 Cumberland St, Ottawa, ON K1N 6N5, Canada.
³ Division of Endocrinology and Metabolism, Department of Pediatrics, Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, ON K1H 8L1, Canada.
⁴ Department of Pediatrics, University of Alberta, 116 St & 85 Av, Edmonton, AB T6G 2R3, Canada.
⁵ Department of surgery, Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, ON K1H 8L1, Canada.
⁶ Department of Genetics, Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, ON K1H 8L1, Canada.
⁷ Department of Medical Genetics and Genomics, Faculty of Medicine, University of Ottawa, 550 Cumberland St, Ottawa, ON K1N 6N5, Canada.
⁸ Shriners Hospital for Children, 1003 Decarie Blvd, Montréal, QC H4A 0A9, Canada.
⁹ Department of Pediatrics, Faculty of Medicine and Health Sciences, McGill University, 805 rue Sherbrooke O, Montréal, Quebec H3A 0B9, Canada.
¹⁰ Department of Medical Imaging, Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, ON K1H 8L1, Canada.

Abstract

Cutaneous-skeletal hypophosphatemia syndrome (CSHS) is a rare bone disorder featuring fibroblast growth factor-23 (FGF23)-mediated hypophosphatemic rickets. We report a 2-year, 10-month-old girl with CSHS treated with burosumab, a novel human monoclonal antibody targeting FGF23. This approach was associated with rickets healing, improvement in growth and lower limb deformity, and clinically significant benefit to her functional mobility and motor development. This case report provides evidence for the effective use of FGF23-neutralizing antibody therapy beyond the classic FGF23-mediated disorders of X-linked hypophosphatemia and tumor-induced osteomalacia.

Keywords: Burosumab; Child; Conventional treatment; Cutaneous-skeletal hypophosphatemia syndrome; Fibroblast growth factor-23; Hypophosphatemic rickets.

Publication types

Case Reports