This study has been important in establishing synthetic human parathyroid hormone 1-34 (PTH) as a beneficial treatment for hypoparathyroidism, superior to conventional therapy with calcium and calcitriol. Providing synthetic human parathyroid hormone 1-34 (PTH) to patients who are unresponsive to conventional therapy has enabled severe cases of hypoparathyroidism to be managed effectively with the investigational drug, PTH. The primary goals of this study are to (1) provide long-term PTH therapy to patients who do not respond to conventional therapy; (2) understand the long-term effect of therapeutic PTH replacement on kidney function and bone mineral density; (3) study and track linear growth and bone accrual in children with hypoparathyroidism. (4) determine if subjects reach a normal level of peak bone mass and if the timing of this is comparable to normal age-matched healthy controls.
Vitamin D and its analogs, the conventional treatment for hypoparathyroidism, are associated with chronic hypercalciuria due to their lack of calcium-retaining effect in the kidney. This side effect usually occurs even while maintaining the serum calcium in the normal range and may lead to calcium deposition in the kidney (nephrocalcinosis) and renal insufficiency. This study examines the long-term effects of subcutaneous parathyroid hormone (PTH) therapy on calcium metabolism, bone, and renal function. Our previous short-term pilot study comparing subcutaneous PTH with calcitriol demonstrated a significant decrease in urinary calcium excretion during PTH therapy. Based upon these results, we hypothesized that treatment with PTH is more physiologic and provides improved long-term metabolic control. Additionally, treatment with PTH may avoid the adverse side effects on the kidney that are associated with conventional therapy. Patients initially come to the Clinical Center for a two week inpatient evaluation. Subsequent follow-up will occur semiannually on an outpatient basis.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
Enrollment
27
twice daily subcutaneous injections
Twice daily oral calcitriol with 1000 mg Calcium carbonate supplementation
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States
Serum Calcium Level
Measurements were taken 1 hour before the morning dose of PTH or, calcitriol and calcium; UOM = mmol/liter, normal range 2.05-2.5. Measurements were obtained on three successive days (three separate measures) semiannually at the NIH CC for each protocol subject. The average data are the average of these three semi-annual data points for each subject which are then averaged across all the semi-annual means for all subjects within each arm over the three years of study.
Time frame: 3 years
Urine Calcium Excretion Level
Measurements were taken1 hour before the morning dose of PTH or, calcitriol and calcium; UOM = mmol/24 h, normal range 1.25-6.25. Measurements were obtained on three successive days (three separate measures) semiannually at the NIH CC for each protocol subject. The average data are the average of these three semi-annual data points for each subject which are then averaged across all the semi-annual means for all subjects within each arm over the three years of study.
Time frame: 3 years
Serum 1,25-hydroxyvitamin D Level
Measurements were taken 1 hour before the morning dose of PTH or, calcitriol and calcium; UOM = pg/ml. Measurements were obtained on three successive days (three separate measures) semiannually at the NIH CC for each protocol subject. The average data are the average of these three semi-annual data points for each subject which are then averaged across all the semi-annual means for all subjects within each arm over the three years of study.
Time frame: 3 years
Serum 25-hydroxyvitamin D Level
Measurements were taken 1 hour before the morning dose of PTH or, calcitriol and calcium; UOM = ng/ml. Measurements were obtained on three successive days (three separate measures) semiannually at the NIH CC for each protocol subject. The average data are the average of these three semi-annual data points for each subject which are then averaged across all the semi-annual means for all subjects within each arm over the three years of study.
Time frame: 3 years
Serum Magnesium Level
Measurements were taken 1 hour before the morning dose of PTH or, calcitriol and calcium; UOM = mmol/liter, normal range 0.65-1.05. Measurements were obtained on three successive days (three separate measures) semiannually at the NIH CC for each protocol subject. The average data are the average of these three semi-annual data points for each subject which are then averaged across all the semi-annual means for all subjects within each arm over the three years of study.
Time frame: 3 years
Serum Phosphorus Level
Measurements were taken 1 hour before the morning dose of PTH or, calcitriol and calcium; UOM = mmol/liter, normal range 0.7-1.4. Measurements were obtained on three successive days (three separate measures) semiannually at the NIH CC for each protocol subject. The average data are the average of these three semi-annual data points for each subject which are then averaged across all the semi-annual means for all subjects within each arm over the three years of study.
Time frame: 3 years
Urinary Creatinine Clearance
Measurements were taken 1 hour before the morning dose of PTH or, calcitriol and calcium; UOM = ml/min, normal range 90-125. Measurements were obtained on three successive days (three separate measures) semiannually at the NIH CC for each protocol subject. The average data are the average of these three semi-annual data points for each subject which are then averaged across all the semi-annual means for all subjects within each arm over the three years of study.
Time frame: 3 years
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