Early Effects of Parathyroid Hormone (PTH) on the Proximal Femur
Information source: Health Research, Inc.
ClinicalTrials.gov processed this data on August 20, 2015 Link to the current ClinicalTrials.gov record.
Condition(s) targeted: Osteoporosis
Intervention: Teriparatide (Drug); placebo (Other)
Phase: N/A
Status: Active, not recruiting
Sponsored by: Health Research, Inc. Official(s) and/or principal investigator(s): Felicia Cosman, M.D., Principal Investigator, Affiliation: Helen Hayes Hospital
Summary
Teriparatide is a potent osteoporosis medication that helps prevent fractures, however, the
investigators know little about its effect on the hip. The investigators will evaluate hip
bone samples from patients treated with teriparatide before undergoing hip replacement. The
information will help us understand how teriparatide might help reduce hip fracture risk.
Clinical Details
Official title: Early Effects of PTH on the Proximal Femur
Study design: Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary outcome: Bone formation rate
Secondary outcome: Blood samples will be analyzed for indices of bone formation (serum P1NP) and resorption (serum CTX) after treatment with placebo or teriparatide Biochemical markers of bone
Detailed description:
Osteoporosis with consequent hip fractures causes substantial disability, morbidity and
mortality. Teriparatide (TPTD), the aminoterminal fragment of parathyroid hormone (PTH),
increases bone mineral density (BMD) and bone strength and reduces fracture incidence
throughout the skeleton, but data confirming specific efficacy against hip fracture will
never be available. Histomorphometric studies after 18-36 months of TPTD treatment show
improvements in bone volume and structure in the iliac crest. Both biochemical and
histomorphometric investigations of the iliac crest at very early time points (within 4-6
weeks of administration) show that bone formation is dramatically stimulated. Apart from
the beneficial effect of TPTD on bone density and bone strength by finite element analysis
at the hip, nothing is known about the mechanism of the effect of TPTD on the proximal
femur. While BMD changes are smaller and slower in the hip in response to TPTD than in the
spine, it is possible that stimulation of bone formation on the periosteal bone surface
could result in expansion of bone size, obscuring the increase in non-invasively measured
BMD. The current study will provide evidence for or against this possible TPTD-induced
periosteal expansion. From a clinical perspective, it is unclear whether TPTD would be
preferable to other osteoporosis medications, such as zoledronic acid, in patients at high
risk for hip fracture. TPTD induced bone formation in the femur would be expected to
improve bone strength and would provide a mechanistic basis for the use of TPTD in patients
at high risk of hip fracture. The proposed project is the only practical and ethical way to
obtain information on the effects of TPTD on bone formation in the proximal femur in humans.
In patients undergoing total hip arthroplasty (THA) for degenerative joint disease, the hip
samples of greatest interest are extracted routinely during the procedure. At the same
time, an iliac crest biopsy can be taken with minimal added time and risk. The protocol has
the following Specific Aims:
In patients undergoing elective, noncemented total hip arthroplasty (THA): 1. To determine
the early effects of 1-34hPTH (teriparatide; TPTD 20 mcg) vs placebo, administered
subcutaneously daily for 6 weeks, on histomorphometric indices of bone formation in
cancellous and cortical bone of the proximal femur (femoral neck and intertrochanteric bone)
and iliac crest. 2. To evaluate the association between changes in biochemical indices of
bone turnover and histomorphometric indices of bone formation in the proximal femur (femoral
neck and intertrochanteric bone) and iliac crest over 6 weeks of treatment with TPTD vs.
placebo. 3. To determine if circulating osteoblast precursor cells increase over 6 weeks of
treatment with TPTD vs Placebo and to compare the change in size of this osteoblast
precursor pool with the change in a biochemical marker of bone formation and indices of bone
formation in the femur and iliac crest.
Eligibility
Minimum age: 50 Years.
Maximum age: 90 Years.
Gender(s): Both.
Criteria:
- Age 50-90 years old.
- Male or postmenopausal (women who have had no menses for one year)
- Degenerative joint disease of the hip (osteoarthritis) requiring total hip
arthroplasty, based on radiologic and clinical impression.
Exclusion Criteria:
- Any contraindications to use of TPTD.
- Age younger than 50, greater than 90 years old.
- Metabolic bone disease other than osteoporosis.
- History of hyperparathyroidism without surgical correction.
- Unexplained hypercalcemia.
- Paget's disease (or unexplained elevated bone alkaline phosphatase level).
- History of any metastatic cancer or osteosarcoma.
- Prior radiation treatment.
- Secondary hyperparathyroidism due to vitamin D deficiency or renal disease. Active
hyperthyroidism or excessive thyroid hormone replacement (with TSH below normal
range).
Locations and Contacts
Helen Hayes Hospital, West Haverstraw, New York 10993, United States
Additional Information
Starting date: August 2010
Last updated: March 17, 2015
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