CASR and hyperphosphatemia: However, the present study involved single dose administration of NPS 2143, and repetitive dosing studies are required to confirm the efficacy of calcilytic compounds in inducing sustained increases in circulating calcium and PTH concentrations in the setting of ADH1 and to determine whether these CaSR-targeted drugs may also ameliorate the hyperphosphatemia and hypercalciuria associated with this disorder.