Imanishi Y, Ito N, Rhee Y, et al. - Clinical picture exhibited by patients with tumor‐induced osteomalacia (TIO), an acquired paraneoplastic condition characterized by osteomalacia due to hypophosphatemia, is similar to that of patients with X‐linked hypophosphatemic rickets/osteomalacia (XLH). Given the effectiveness of the human monoclonal anti‐fibroblast growth factor 23 (FGF23) antibody burosumab (KRN23) in increasing serum phosphate and improving bone turnover, fracture healing, pain, and physical function in XLH patients, researchers sought to determine the effectiveness of burosumab as treatment for TIO. An interim analysis of a multicenter, open‐label, intraindividual dose‐adjustment study of burosumab (0.3 to 2.0 mg/kg every 4 weeks) in Japanese and Korean TIO patients has been reported in this study. Burosumab treatment was provided to 13 patients, of whom 4 underwent bone biopsy. The mean dose was nearly 1.0 mg/kg after week 112. The interim results of this first study of burosumab to treat TIO patients indicate this drug as potentially beneficial for patients with unresectable tumors.