• INCLUSION CRITERIA:

  1. Age eligibility at screening:

     1. Adult female aged 18 to 45 years,
     2. Adult male aged 18 to 50 years,
     3. Adolescent female with a bone age greater than or equal to 14 years (x-ray of the hand and wrist), or
     4. Adolescent male with a bone age greater than or equal to 16 years (x-ray of the hand and wrist).
  2. Physician-diagnosed hypoparathyroidism of at least 1-year duration, confirmed by medical record review. The investigators will confirm the diagnosis during the screening visit at which time the subject must have an intact PTH < 30 pg/mL.
  3. Willing to provide informed consent

EXCLUSION CRITERIA:

1. Moderate to severe hepatic disease defined as hepatic transaminases (ALT and AST) > 2 times the upper limit of normal
2. Severe renal insufficiency defined as a calculated GFR < 25 mL/min/1.73 m2, using the Cockcroft-Gault equation15 in subjects < 18 and the CKD-EPI equation in subjects greater than or equal to 18.
3. Allergy or intolerance to tetracycline antibiotics
4. Pregnant or lactating. Peri-or post-menopausal as defined by no menses for > 6 months and an FSH > 20 U/L at the screening and/or baseline visits.
5. Chronic diseases that might affect mineral metabolism such as diabetes, celiac disease, Crohn's disease, Cushing's syndrome, or adrenal insufficiency
6. Concurrent treatment with doses of thyroid hormone intended to suppress thyroid stimulating hormone below the assay's detection limit or persistent thyroid cancer
7. History of a skeletal disease unrelated to hypoparathyroidism, such as osteoporosis or low bone density [defined as a DXA Z-Score (children or adults) or T-score (adults only) < -2], osteosarcoma, Paget's disease, or metastatic bone disease
8. History of treatment with bisphosphonates, calcitonin, tamoxifen, selective-estrogen receptor modulators, or directed skeletal irradiation
9. Use of oral or intravenous corticosteroids for more than 3 weeks within the last 6 months
10. Use of depot medroxyprogesterone for contraception within the past 12 month
11. Chronic inadequate biochemical control with conventional therapy and/or calcium infusion dependent
12. Seizure disorder requiring antiepileptic medications
13. Treatment with PTH for more than 2 weeks prior to study entry
14. Any cognitive impairment that limits the subject's or the subject's legally authorized representative's ability to understand the protocol, provide informed consent or assent, or to comply with the protocol procedures
15. Unwillingness or inability to comply with protocol procedures