Protocol Number: 07-D-0016

Title:

Effects of Calcitriol vs. PTH Replacement Therapy on Bone in Patients with Hypoparathyroidism

Number:

07-D-0016

Summary:

This study will determine whether a synthetic form of human parathyroid hormone (PTH) can control hypoparathyroidism and will examine the drug's effects on bone. Blood calcium and phosphate levels in patients with hypoparathyroidism are difficult to control with the current standard treatment of calcitriol and calcium supplementation. Calcium levels in the urine may be elevated at the same time that blood calcium levels are normal. This spilling of excessive calcium into the urine can lead to kidney damage.

Patients between 9 and 55 years of age with hypoparathyroidism may be eligible for this study. Participants

take standard calcitriol therapy for the first year of the study and start PTH after 1 year. After 1 year on PTH, they are given the option to continue the drug for an additional 3 years.

Patients are admitted to the NIH Clinical Center for 4-6 days at the start of the study, at the end of the first year, and at the end of the second year (and at year 5 for those who continue on PTH for an additional 3 years) for the following procedures:

" Daily 24-hour urine collection.

" Daily blood draw for calcium and phosphorous levels and for calcium-regulating hormones.

" Blood draw every 2 hours for 24 hours to measure blood calcium, phosphorus, and magnesium levels (admission 3 only). For this test blood samples are collected through a catheter (plastic tube) placed in a vein in the arm or hand to avoid multiple needle sticks.

" Questionnaire and 6-minute walk test to determine fatigue

" Bone biopsy to test treatment response. Before the biopsy, patients are given a regimen of the antibiotic tetracycline or demeclocycline. The drug is absorbed by the bone, "labeling" it in a way that permits investigators to learn more about the bone's biology. For the biopsy, the patient is given a sedative to cause drowsiness. The skin over the hipbone is numbed with an injection of anesthetic into the skin, through the underlying tissues, and onto the surface of the bone. A larger needle is then inserted into the bone itself, and a sample of bone tissue is withdrawn through the needle. More sedative or anesthetic may be given to lessen any pain.

Every week for the first month of the study and then twice a month, patients go to a laboratory for a 24-hour urine collection. Every 6 months, they come to the NIH outpatient clinic for a physical exam, blood and urine tests, and a dual energy X-ray absorptiometry (DXA) scan to measure bone density.

Sponsoring Institute:

National Institute of Dental And Craniofacial Research (NIDCR)

Recruitment Detail

Type: No longer recruiting/follow-up only

Gender: Male & Female

Referral Letter Required: No

Population Exclusion(s): None

Eligibility Criteria: This study is not currently recruiting new subjects. If you have questions about participating in a study, please contact the Patient Recruitment and Public Liaison Office, CC.

Special Instructions:

Currently Not Provided

Keyword(s):

Parathyroid

Calcitriol

Bone Density

Skeletal Biology

Bone Growth

Recruitment Keyword(s):

Hypoparathyroidism

Bone Density

Condition(s):

Hypoparathyroidism

Investigational Drug(s):

Synthetic Human PTH 1-34

Investigational Device(s):

None

Interventions:

Drug: Synthetic Human PTH 1-34

Supporting Site:

National Institute of Dental and Craniofacial Research

Contact(s):

This study is not currently recruiting new subjects. If you have questions about participating in a study, please contact the Patient Recruitment and Public Liaison Office, CC.

Citation(s):

Chan JC, Young RB, Alon U, Mamunes P. Hypercalcemia in children with disorders of calcium and phosphate metabolism during long-term treatment with 1,25-dihydroxyvitamin-D3. Pediatrics. 1983 Aug;72(2):225-33. No abstract available.

Chan JC, Young RB, Hartenberg MA, Chinchilli VM. Calcium and phosphate metabolism in children with idiopathic hypoparathyroidism or pseudohypoparathyroidism: effects of 1,25-dihydroxyvitamin D3. J Pediatr. 1985 Mar;106(3):421-6.

Christiansen C, Rodbro P, Christensen MS, Hartnack B, Transbol I. Deterioration of renal function during treatment of chronic renal failure with 1,25-dihydroxycholecalciferol. Lancet. 1978 Sep 30;2(8092 Pt 1):700-3.

• Questions about participating in a study, please contact the Patient Recruitment and Public Liaison Office, CC.
• Technical questions regarding the Clinical Center web site, please contact the Department of Networks and Applications, CC.

Search The Studies | Help | Questions |
Clinical Center Home | NIH Home

National Institutes of Health Clinical Center
Bethesda, Maryland 20892. Last update: 09/16/2008