EneboPTH Meets Primary Endpoint

The primary endpoint is a composite of normalisation of albumin-adjusted serum calcium levels and independence from active vitamin D and oral calcium therapy.

Eneboparatide was well tolerated. After the 24-week randomised treatment period, all patients receive eneboparatide in the ongoing long-term extension period until 52 weeks. Full efficacy and safety data will be analysed at 52 weeks. Alexion plans to share these data with global health authorities and present them at forthcoming medical meetings.

Marc Dunoyer, Chief Executive Officer, Alexion, AstraZeneca Rare Disease, said: “People living with HypoPT, a rare endocrine disease, are often at increased risk of hypercalciuria, osteopenia and osteoporosis, and these results from the CALYPSO trial underscore eneboparatide’s potential to be another option for these patients. We look forward to reviewing clinical results at 52 weeks to fully characterise the risk-benefit profile.”

HypoPT is a rare endocrine disease caused by a deficiency of PTH and characterised by impaired regulation of calcium and phosphate levels in the blood. This dysregulation of the physiological action of PTH can lead to clinical manifestations, including negative impact on the kidney and bone. HypoPT is one of the largest known rare diseases, affecting over 200,000 people in the United States and the European Union, approximately 80% of whom are women.

CALYPSO is a global Phase III, randomised, double-blind, placebo-controlled, multicentre trial designed to evaluate the efficacy and safety of eneboparatide in adults with chronic hypoparathyroidism. A total of 202 patients treated with standard of care (active vitamin D and oral calcium supplementation) were randomised in a 2:1 ratio to receive eneboparatide or placebo. The primary efficacy endpoint is a composite of the proportion of patients that achieve albumin-adjusted serum calcium within the normal range and independence from standard of care after 24 weeks of treatment. The key secondary efficacy endpoints include normalisation of 24-hour urinary calcium in patients with hypercalciuria at baseline and assessment of patient-reported outcomes that reflect physical symptoms and impact on quality of life. After the 24-week randomised main treatment period, all patients receive eneboparatide treatment in the ongoing long-term extension period.