Secondary hyperparathyroidism

Mimpara has been compared with placebo (a dummy treatment) in three main studies involving 1,136 adults with secondary hyperparathyroidism who were on dialysis because they had a serious kidney disease. The main measure of effectiveness was the number of patients who had a parathyroid hormone level below 250 micrograms per litre after 6 months.

In these studies, about 40% of the patients taking Mimpara had parathyroid hormone levels below 250 micrograms per litre, compared with about 6% of those taking placebo. Mimpara brought about a 42% reduction in average PTH levels compared with an increase of 8% in patients taking placebo.

In children, Mimpara was compared with placebo in a study involving 43 children aged 6 to 18 years with serious kidney disease. The main measure of effectiveness was the reduction of PTH levels by 30%. In this study, 55% (12 out of 22) children given Mimpara achieved a 30% reduction of PTH levels, compared with 19% (4 out of 21) children given placebo.

Parathyroid gland cancer or primary hyperparathyroidism

Mimpara has been studied in a study involving 46 patients with hypercalcaemia, including 29 with parathyroid cancer, and 17 with primary hyperparathyroidism who could not have their parathyroid glands removed or in whom surgery to remove the parathyroid glands was not effective. The main measure of effectiveness was the number of patients whose blood calcium levels fell by more than 1 mg per decilitre by the time a maintenance dose had been found (between two and 16 weeks after the start of the study). The study continued for over three years. Mimpara produced a decrease in blood calcium of more than 1 mg/dl in 62% of the cancer patients (18 out of 29) and in 88% of the patients with primary hyperparathyroidism (15 out of 17).

A further three studies compared Mimpara with placebo in a total of 136 patients with primary hyperparathyroidism over up to a year. Of these, 45 went on to a fourth, long-term study looking at the effectiveness of Mimpara over a total of almost six years. The results supported the use of Mimpara for hypercalcaemia in patients with primary hyperparathyroidism.