Imel EA, et al. - Through a randomized, active-controlled, open-label, phase 3 trial at 16 clinical sites with 61 patients with pediatric X-linked hypophosphatemia, researchers compared the effectiveness and safety of continuing conventional therapy (oral phosphate and active vitamin D) vs switching to burosumab, a fully human monoclonal antibody against fibroblast growth factor 23. Three serious adverse events occurred in each group, all unrelated to treatment and were resolved. Treatment-emergent adverse events considered possibly, probably, or definitely related to treatment by the investigator occurred more frequently with burosumab. In rickets severity, growth, and biochemistries, treatment with burosumab led to significantly greater clinical improvements in children with X-linked hypophosphatemia vs those continuing conventional therapy. Patients in the burosumab group had significantly greater improvement in Radiographic Global Impression of Change global score vs patients in the conventional therapy group at week 40.