This study aims to test MBX 2109, a medicine given once a week, to help people with hypoparathyroidism. Hypoparathyroidism is a condition where the parathyroid glands in the neck don't make enough parathyroid hormone (PTH), which is important for controlling calcium levels in the blood. MBX 2109 is being tested to see if it can help keep calcium levels normal without extra vitamin D or calcium supplements.

• Participants should be at least 18 years old with certain types of hypoparathyroidism.
• They must not have other conditions that affect calcium levels or recently used certain medications.
• Women who can have children and sexually active men must use birth control during the study.

Before joining, participants will need to have normal blood tests and agree to follow study rules. They should not have recent serious health issues, certain diseases, or a history of drug/alcohol problems. This study will help find out if MBX 2109 is safe and effective for managing hypoparathyroidism.