Study of KRN23 (Burosumab), a Recombinant Fully Human Monoclonal Antibody Against Fibroblast Growth Factor 23 (FGF23), in Pediatric Subjects With X-linked Hypophosphatemia (XLH)

Summary

The objectives of the study are to: * Identify a dose and dosing regimen of burosumab, based on safety and pharmacodynamic (PD) effect, in pediatric XLH participants * Establish the safety profile of burosumab for the treatment of children with XLH including ectopic mineralization risk, cardiovascular effects, and immunogenicity profile * Characterize the pharmacokinetic (PK)/PD profile of the KRN23 doses tested in the monthly (Q4) and biweekly (Q2) dose regimens in pediatric XLH patients * Determine the PD effects of burosumab treatment on markers of bone health in pediatric XLH patients * Obtain a preliminary assessment of the clinical effects of burosumab on bone health and deformity, muscle strength, and motor function * Obtain a preliminary assessment of the effects of burosumab on participant-reported outcomes, including pain, disability, and quality of life in pediatric XLH patients * Evaluate the long-term safety and efficacy of burosumab

Timeline

Start

2014-07-02

Primary completion

2018-10-30

Completion

2018-10-30

Publications

• Portale AA, Ward L, Dahir K, Florenzano P, Ing SW, Jan de Beur SM, Martin RM, Meza-Martinez AI, Paloian N, Ashraf A, Dixon BP, Khan A, Langman C, Chen A, Wang C, Roberts MS, Tandon PK, Bedrosian C, Imel EA. Nephrocalcinosis and kidney function in children and adults with X-linked hypophosphatemia: baseline results from a large longitudinal study. J Bone Miner Res. 2024 Sep 26;39(10):1493-1502. doi: 10.1093/jbmr/zjae127.
• Linglart A, Imel EA, Whyte MP, Portale AA, Hogler W, Boot AM, Padidela R, Van't Hoff W, Gottesman GS, Chen A, Skrinar A, Scott Roberts M, Carpenter TO. Sustained Efficacy and Safety of Burosumab, a Monoclonal Antibody to FGF23, in Children With X-Linked Hypophosphatemia. J Clin Endocrinol Metab. 2022 Feb 17;107(3):813-824. doi: 10.1210/clinem/dgab729.
• Mao M, Carpenter TO, Whyte MP, Skrinar A, Chen CY, San Martin J, Rogol AD. Growth Curves for Children with X-linked Hypophosphatemia. J Clin Endocrinol Metab. 2020 Oct 1;105(10):3243-9. doi: 10.1210/clinem/dgaa495.
• Carpenter TO, Whyte MP, Imel EA, Boot AM, Hogler W, Linglart A, Padidela R, Van't Hoff W, Mao M, Chen CY, Skrinar A, Kakkis E, San Martin J, Portale AA. Burosumab Therapy in Children with X-Linked Hypophosphatemia. N Engl J Med. 2018 May 24;378(21):1987-1998. doi: 10.1056/NEJMoa1714641.

Drugs

Indications