This study is testing the long-term safety of a drug called MBX 2109 for people with hypoparathyroidism. Hypoparathyroidism is a condition where the body doesn’t make enough of a hormone called parathyroid hormone, which helps control calcium levels. Participants must have finished a previous 12-week study with MBX 2109. This drug is given once a week to help keep calcium levels normal without needing extra vitamin D or high calcium supplements. To join, you must be an adult who completed the earlier study, have a specific type of hypoparathyroidism, and agree to the study's terms and visits.

• Study duration and visits are based on long-term follow-up.
• Participants need to self-administer the medication.
• Potential for reduced calcium supplement intake.