Atypical Femur FractureNCT04110795
Personalizing Osteoporosis Care: Clinical & Genetic Risk Factors for AFFs
An observational study of Atypical Femur Fracture, run by University Health Network, Toronto at 3 sites in Canada.
Trial summary
The overall objective of this project is to identify clinical and genetic risk factors for Atypical Femur Fractures (AFFs) in Anti-resorptive therapy (ART) users by conducting a case control study of 330 cases of AFFs and 660 controls without AFFs matched for age, sex, race and duration of ART. Read more about this study
- Who is it for?
- Ages 18 years and older, women onlyHealthy volunteers can take part
- Conditions the study is for
- Atypical Femur Fracture
- How many people
- 1,200 participants
- Where
- 3 sitesCanada
- Study dates
- 25 Jun 2018to 31 Dec 2028
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- Women only
- Healthy volunteers accepted
- Adult, Older adult
Study population: Community based population in Ontario and British Columbia Canada
Who may be able to join
- Cases: Have experienced a confirmed, documented Atypical femur fracture
- Controls: currently on anti-resorptive therapy, matches AFF case by age, race and length of ART use
Who cannot join
- -
Trial locations and contacts
3 sites in 1 country.
Canada3 sites
Adachi Medical Centre
Hamilton, Ontario, L8N 1Y2
Bone Research & Education Centre
Oakville, Ontario, L6M 1M1
University Health Network, TGH
Toronto, Ontario, M5G 2C4
About this study
Official title: Personalizing Osteoporosis Care: Clinical & Genetic Risk Factors for Atypical Femur Fractures
The overall objective of this project is to identify clinical and genetic risk factors for Atypical Femur Fractures (AFFs) in Anti-resorptive therapy (ART) users by conducting a case control study of 330 cases of AFFs and 660 controls without AFFs matched for age, sex, race and duration of ART.
Read the detailed description
Antiresorptive therapy (ART) drugs are effective osteoporosis treatment and help decrease osteoporosis-related fractures. However, their long-term use has been associated with rare but serious atypical femur fractures (AFFs). Fear of these side effects has caused a substantial decline in the use of these effective drugs and rising fracture rates. The investigators propose to compare 330 cases of people with AFFs to 660 matched controls to explore similarities and differences in (1) clinical findings, such as type of ART and length of use, prior fracture, bone density, femur geometry, etc., and (2) genetic variants, and then (3) to validate the top few genetic variants to see if they are indeed present in an additional group of 100 AFF patients and not present in 100 control subjects. This study will determine clinical and genetic risk factors for these debilitating atypical fractures such that at-risk patients in the future can be treated differently to avoid them.
- Conditions
- Atypical Femur Fracture
- Being tested
- No Intervention
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
No InterventionOther
No Intervention
| Study group | Role | What they receive |
|---|---|---|
| Cases | Atypical Femur fracture cases Receives: Other: No Intervention | |
| Control | matched to AFF cases by race, age, length of ART use Receives: Other: No Intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
Associations between AFF and clinical Risk Factor
Associations between AFFs and clinical risk factors
Measured: baseline
Associations between AFF and common genetic variants
Associations of common genetic variants among patients with AFFs
Measured: baseline
Validation of top genetic variants
To validate the top few genetic variants identified in the above case-control study in a separate cohort of 100 cases and 100 controls.
Measured: baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Oct 2019
- Study start25 Jun 2018
- Primary completion31 Dec 2027 (estimated)
- Study completion31 Dec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Atypical Femur FractureStudies of the same condition, open and under way.
- More trials run by University Health Network, TorontoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 1,200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Health Network, Toronto
- Sponsor type
- University, hospital or other
- Collaborators
- Canadian Institutes of Health Research (CIHR)
- Responsible party
- Sponsor
- Investigators
- Angela M Cheung, MD PhD, Principal investigator, University Health Network, Toronto
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04110795
- Sponsor's protocol ID
- 18-6171
- Status last verified
- May 2026
- First submitted
- 25 Sep 2019
- Last updated
- 11 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 11 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Personalizing Osteoporosis Care: Clinical & Genetic Risk Factors for Atypical Femur Fractures
- ClinicalTrials.gov ID
- NCT04110795
- Acronym / sponsor ID
- 18-6171
- Conditions
- Atypical Femur Fracture
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 1,200 participants (estimated)
- Lead sponsor
- University Health Network, TorontoUniversity, hospital or other
- Collaborators
- Canadian Institutes of Health Research (CIHR)
- Study start
- 25 Jun 2018 (actual)
- Primary completion
- 31 Dec 2027 (estimated)
- Study completion
- 31 Dec 2028 (estimated)
- First posted
- 1 Oct 2019 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The overall objective of this project is to identify clinical and genetic risk factors for Atypical Femur Fractures (AFFs) in Anti-resorptive therapy (ART) users by conducting a case control study of 330 cases of AFFs and 660 controls without AFFs matched for age, sex, race and duration of ART.
Detailed description
Antiresorptive therapy (ART) drugs are effective osteoporosis treatment and help decrease osteoporosis-related fractures. However, their long-term use has been associated with rare but serious atypical femur fractures (AFFs). Fear of these side effects has caused a substantial decline in the use of these effective drugs and rising fracture rates. The investigators propose to compare 330 cases of people with AFFs to 660 matched controls to explore similarities and differences in (1) clinical findings, such as type of ART and length of use, prior fracture, bone density, femur geometry, etc., and (2) genetic variants, and then (3) to validate the top few genetic variants to see if they are indeed present in an additional group of 100 AFF patients and not present in 100 control subjects. This study will determine clinical and genetic risk factors for these debilitating atypical fractures such that at-risk patients in the future can be treated differently to avoid them.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Cases | – | Other: No InterventionAtypical Femur fracture cases |
| Control | – | Other: No Interventionmatched to AFF cases by race, age, length of ART use |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Community based population in Ontario and British Columbia Canada
Key inclusion criteria (2 listed)
- Cases: Have experienced a confirmed, documented Atypical femur fracture
- Controls: currently on anti-resorptive therapy, matches AFF case by age, race and length of ART use
Key exclusion criteria (1 listed)
- -
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| No InterventionNo Intervention | Other | Cases, Control |
Primary outcome
Associations between AFF and clinical Risk Factor
Time frame: baseline
Associations between AFFs and clinical risk factors
Associations between AFF and common genetic variants
Time frame: baseline
Associations of common genetic variants among patients with AFFs
Validation of top genetic variants
Time frame: baseline
To validate the top few genetic variants identified in the above case-control study in a separate cohort of 100 cases and 100 controls.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 May 2026.
- Individual participant dataSharing planned: Undecided
Related trials for Atypical Femur Fracture
Active, not recruitingObservational study
Quebec Registry for Atypical Femur Fractures
Atypical Femur Fracture
RecruitingObservational study
Atypical Fracture Cohort Study
Atypical Femur Fracture, Atypical Subtrochanteric Fracture
Active, not recruitingObservational study
Evaluation of IVA (SE Femur Scans) to Identify Incomplete AFFs
Atypical Femur Fracture
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Angela M Cheung, MD PhD principal investigator
University Health Network, Toronto
3 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Atypical Femur Fracture, run by University Health Network, Toronto at 3 sites in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 11 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 3 sites in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Associations between AFF and clinical Risk Factor (time frame: baseline). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 May 2026.