Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT01155232 |
| Other study ID # |
04-0655 |
| Secondary ID |
|
| Status |
Recruiting |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
November 2004 |
| Est. completion date |
January 2026 |
Study information
| Verified date |
May 2023 |
| Source |
University Health Network, Toronto |
| Contact |
Jessica Chang, RN |
| Phone |
416-340-4800 |
| Email |
jessica.chang[@]uhn.on.ca |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
Teriparatide (PTH) is the only bone formation therapy that has been approved for the
treatment of postmenopausal osteoporosis in Canada. Osteoporosis is currently diagnosed using
a bone mineral density (BMD) scan, which measures the amount of mineral (calcium etc) in
bones (the higher the amount of mineral, the lower the fracture risk). Although BMD is linked
to bone strength and is used to measure fracture risk, it does not give information on bone
structure (called bone geometry) which can also tell us a great deal about fracture risks.
Clinical trials have shown that teriparatide increases BMD at the lumbar spine and total hip,
while BMD at the forearm may decrease after 20 months of therapy. However, bone biopsies of
the pelvis done on people taking teriparatide show improvement of bone geometry (ie bone
thickness and increased trabeculae (small interconnecting rods of bone), suggesting that a
change in bone geometry at the wrist may be occurring as well. Currently, there is a new
technology, high resolution pQCT (HR-pQCT) that can assess bone geometry without a biopsy.
Since bone strength is affected both by BMD and bone structure (as well as other material
properties), our group is interested in examining changes in bone geometry at the radius and
tibia in men and women with osteoporosis who receives 24 months of teriparatide therapy.
The investigators believe that this new approach of measuring bone strength will help us
better understand the mechanisms of therapeutic efficacy of teriparatide. In addition,
measuring indices of bone strength such as the material composition (bone mineral content or
BMD) and structural properties of bone (size and shape, and microarchitecture) may provide
more data about the mechanisms of how teriparatide treatment can decrease fracture risk. In
the end, this data will benefit and improve patient care by allowing us to show patients and
their providers that whether BMD increases, decreases or stay the same, there are changes in
their bone geometric structure with teriparatide therapy that increases bone strength.
Description:
Teriparatide (PTH) is the only bone formation therapy that has been approved for the
treatment of postmenopausal osteoporosis in Canada. Randomized controlled trials have shown
that teriparatide increases bone mineral density (BMD) at the lumbar spine and total hip,
while BMD at the forearm may decrease after 20 months of therapy. It is believed that the
decline in BMD at the distal radius observed during teriparatide therapy may not be
indicative of decreases in bone strength, but may be a result of increases in the width of
the radius. Teriparatide works by inducing new periosteal bone apposition, which results in
improved bone geometry and increased bone strength that may not be reflected by BMD
measurements. However, there is no published data on bone geometric changes at the radius
either by bone biopsy or by HR-pQCT in patients receiving teriparatide therapy. It is our
intention to fill this gap in knowledge with regard to how teriparatide affects BMD and bone
structure at the radius and tibia in men and women with osteoporosis.
The main objectives of this study are to determine the effect of 24 months of teriparatide
therapy on cortical thickness, trabecular thickness, trabecular number, trabecular separation
and BV/TV, as measured by HR-pQCT (XtremeCT, Scanco Medical, Switzerland) at the radius and
tibia in men and women with osteoporosis. The primary outcome will be cortical thickness; the
other measures will be secondary outcomes. The secondary objective is to determine the effect
of 24 months of teriparatide therapy on moment of inertia, connectivity index, and bone
strength, as measured by the HR-pQCT and calculated using finite element modeling analysis at
the radius and tibia in men and women with osteoporosis.
This is an open label before and after study of a cohort of 100 men and women taking
teriparatide for 24 months. As this is an observational study, study medication will not be
supplied to study participants.
Recruitment of these subjects will be by referral from specialty clinics of the participating
investigators. Participants will undergo two (2) procedures on five (7) separate occasions
(at baseline, 6, 12, 18 and at 24 months, and then post therapy at 36 and 48 months). The
procedures are HR-pQCT and DXA. In addition to the above procedures, subjects will be asked
to complete blood tests which are part of standard clinical practice. Blood will be done both
at baseline, 1 month and at 18 month. A follow up phone call will also be made to the patient
at 1 month to discuss any updates in patient's health status and to ensure that patients
complete the 1 month blood tests.
Understanding the effect of teriparatide on bone geometry and BMD will enable us to better
understand the effect of teriparatide on bone strength at the radius and the tibia, and bone
strength in general, even when the BMD stays the same or decreases after a course of
treatment.
