Cinacalcet as symptomatic treatment of hypercalcaemia in primary hyperparathyroidism prior to surgery

The aim of presented study was to assess the efficacy of cinacalcet in reducing serum calcium concentrations in primary hyperparathyroid (PHPT) patients with hypercalcaemia exceeding 12.5 mg/dL, awaiting parathyroidectomy.

The study included 23 patients with PHPT with hypercalcaemia > 12.5 mg/dL, qualified for surgery. We recorded clinical and biochemical data at baseline, and after every week of treatment. We also monitored adverse events. Cinacalcet was adminis-tered in increasing doses until the corrected serum calcium concentration was 11.3 mg/dL or less, the patient reached the highest possible dosage of 90 mg four times daily, or the patient experienced an adverse event that precluded further dosage increases.

The primary end point of reduction in corrected serum calcium concentration to 11.3 mg/dL was achieved in 19 patients (83%), and normocalcaemia (S-Ca < 10.3 mg/dL) was achieved in 55% of patients. The medication was usually well tolerated (83.4%). Most common adverse events were nausea and vomiting, especially at the beginning of therapy; however, only one patient withdrew from the study because of adverse events.

Cinacalcet rapidly reduced serum calcium in PHPT patients with severe hypercalcaemia and can be useful as a short-term pretreatment prior to surgery, allowing the completion of diagnostics and safe awaiting for operation.