Regpara should be administered with care in the following patients:
Patients with hypocalcaemia: Hypocalcaemia may be aggravated.
Patients with seizure or a history of seizure: It has been reported in overseas studies that seizure occurred in patients with a history of seizure.
Patients with hepatic function disorder: The exposure amount will be increased since cinacalcet is metabolized in the liver.
During treatment with Regpara, sufficient caution should be exercised to avoid hypocalcaemia by periodical measurement of the serum calcium level. If hypocalcaemia occurs or may occur, it should be taken into account to use calcium or vitamin D preparations, as well as to reduce the dose of Regpara (see Dosage & Administration). If administration of calcium or vitamin D preparations is discontinued during treatment with Regpara, caution should be exercised for possible occurrence of hypocalcaemia. Symptoms likely to be associated with hypocalcaemia eg, prolonged QT interval, paresthesia, cramping, feeling unwell, arrhythmia, decreased blood pressure and seizure, etc have been reported in clinical studies on the drug.
At the start of administration and during the dose adjustment period, the patient's symptoms should be frequently monitored and caution should be exercised for possible occurrences of adverse reactions.
Others: In an overseas clinical study in which cinacalcet was used in patients with chronic renal failure accompanied by secondary hyperthyroidism who had not yet started dialysis, it has been reported that the blood calcium level tended to be lower than the lower limit of the normal range (8.4 mg/dL) compared to that in patients receiving dialysis. Use of Regpara in patients not yet on dialysis has not been approved.
It has been reported abroad that adynamic bone disease occurred due to an excessive decrease in PTH following administration of cinacalcet.
It has been reported abroad that hungry bone syndrome accompanied by hypocalcaemia and hypophosphatemia occurred due to a rapid decrease in PTH following administration of cinacalcet.
Use in pregnancy & lactation: It is recommended not to use Regpara in pregnant women or in women who may possibly be pregnant. The drug should be used in such patients only if the anticipated therapeutic benefits outweigh the potential risks associated with the treatment. The safety of Regpara during pregnancy has not been established. Hypocalcaemia, suppressed weight gain and decreased food consumption in mothers, as well as decreased weight in fetuses were observed in animal studies (using rats and rabbits). Furthermore, Regpara was reported to be transferred through the placenta in animal studies (using rats and rabbits).
Treatment with Regpara should be avoided in nursing mothers. When the use is necessary in such women, breastfeeding should be discontinued. In animal studies (using rats), Regpara was reported to be transferred into milk. Furthermore, suppressed weight gain was observed in newborns on breastfeeding.
Use in children: The safety of Regpara in low birth weight infants, newborns, sucklings, infants and children has not been established (no clinical experience).
Use in the elderly: Caution should be exercised when Regpara is administered to patients ≥65 years, because they have been reported to show higher incidences of adverse reactions (prolonged QT intervals in particular) than those younger than 65 years. If any adverse reactions are observed, appropriate measures eg, reducing the dose should be taken.