In addition to the therapy that targets the originating malignancy, the control of elevated serum calcium requires the administration of a bisphosphonate such as intravenous zoledronic acid or subcutaneous denosumab, a human monoclonal antibody which acts as an inhibitor of RANKL (receptor activator of nuclear factor kappa B ligand), as similarly used in PTH-related hypercalcaemia (e.g., primary hyperparathyroidism) [171]. This evidence concerns the gene PTH and primary hyperparathyroidism.