FGF23 and hyperphosphatemia: Therapies involving intravenous iron delivery reduced circulating FGF23 in anemic patients38,52,53 but may manifest side effects, including oxidative stress, liver iron overload, and cardiovascular disease.54 Thus the present work suggests that directly modulating PHD2 function in osteocytes may reduce FGF23 to prevent severe manifestations of FGF23 over expression, but not to a level causing hyperphosphatemia which is associated with negative patient outcomes.55,56