A Clinical Study on the Effect of Discontinuing Alendronate in Postmenopausal Women with Osteoporosis After a Treatment Period Without Fractures

Phase 4

Recruiting

• Conditions: Osteoporosis in Post-menopausal Women
• Interventions: Drug: Alendronate 70mg weekly

• Registration Number: NCT06864130
• Lead Sponsor: Odense University Hospital

Brief Summary

The goal of this clinical trial is to study the effects of discontinuation of Alendronate treatment for three years. The participants are postmenopausal women with osteoporosis, who have had a treatment period without fractures. The study will answer:

* What is the rate of fragility fractures during the study? The hypothesis is that discontinuation of Alendronate after a fracture-free period does not raise the 3-year fracture risk.

* Are there predictors of significant bone loss after discontinuation of Alendronate? The hypothesis is that clinical, biochemical, cellular, or molecular characteristics can predict bone loss.

Researchers will compare the outcomes of discontinuation of Alendronate with continuing treatment. Participants will be randomly assigned to a group.

Participants will:

* Either take alendronate once weekly for three years OR discontinue their treatment

* Visit the clinic at 6 and 18 months for blood samples

* Visit the clinic at the start of the study and after 1, 2, and 3 years for bone scans and blood samples.

Detailed Description

Not available

Study Timeline

• Status Verified: 2025-02
• Study First Submitted: 2025-02-10
• Study Start: 2025-02-21
• Study First Submitted QC: 2025-02-28
• Last Update Submitted: 2025-02-28
• Study First Posted: 2025-03-07
• Last Update Posted: 2025-03-07
• Primary Completion: 2029-03-01
• Study Completion: 2029-09-15

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 1400

Inclusion Criteria

• Female
• Postmenopausal
• Current treatment with Alendronate
• Alendronate treatment >3 år AND no fracture OR
• Alendronate treatment >5 år AND latest low energy fracture > 3 years ago

Exclusion Criteria

• T-score < - 3,5 in hip (total hip or femoral neck) or lumbar spine
• Treatment with systemic glucocorticoids, ongoing or within 12 months
• Uncontrolled inflammatory disease
• Active malignancy
• eGFR < 40 mL/min
• Atypical femur fracture (ever)
• OsteoNecrosis of the Jaw (active)
• Unable to give inform consent

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Discontinuation of Alendronate	Alendronate 70mg weekly	Discontinuation of Alendronate treatment

Primary Outcome Measures

Name	Time	Method
Fragility fractures	From enrollment to the end of the 3 year study period.	Incidence of fragility fractures during the study period

Secondary Outcome Measures

Name	Time	Method
Restart Criteria	From enrollment to the end of the study period at 3 years	The proportion of participants meeting restart criteria during the study period. Restart criteria is defined as: Participants experiencing boneloss exceeding 10% from baseline in any region, one clinical vertebral fracture, two low energy fractures (including morphometric vertebral fracture but excluding fractures of scull, fingers or toes) are withdrawn from the study and offered treatment with alendronate or zoledronic acid after new diagnostic work-up.
Changes in bone mineral density (BMD)	Baseline, 12, 24 and 36 months	Changes in lumbar spine and total hip BMD measured by dual energy X-ray arbsorptiometry. The three follow-up scans will be analyzed by a technician blinded to participant allocation, ie this person will not meet the patient and the patient will not be able see the results of the scans until the final study visit.
Bone turn over marker (P1NP)	Blood samples are performed at baseline, 6, 12, 18, 24, and 36 months.	Fasting blood samples will be performed during the study period to analyze changes in procollagen type I N-terminal propeptide (PINP).
Bone turn over marker (CTX)	Blood samples are performed at baseline, 6, 12, 18, 24, and 36 months.	Fasting blood samples will be performed during the study period to analyze changes in carboxy-terminal collagen crosslinks (CTX).
Adverse Events	From enrollment to the end of the 3 year study period.	At baseline a thoroughly physical examination of the participants and questioning concerning any conditions or diseases will take place. This way the investigators will be able to evaluate possible changes throughout the study. Patients will be interviewed about the occurrence of AEs at each visit from the first trial related activity after the subject has signed the informed consent. Subjects that experience adverse events or develop a disease during the trial period will be managed until the condition is cured or stationary. If this is not the case at the end of the study, subjects will be referred to a relevant physician, e.g. the general practitioner or a specialist, to be followed up.

Trial Locations

Locations (7)

Aalborg University Hospital; 🇩🇰 Aalborg, Denmark

Bispebjerg Hospital; 🇩🇰 Copenhagen, Denmark

Esbjerg Og Grindsted Sygehus; 🇩🇰 Esbjerg, Denmark

Copenhagen University Hospital (Herlev); 🇩🇰 Herlev, Denmark

Nordsjaellands Hospital (Hillerød); 🇩🇰 Hillerød, Denmark

Hvidovre Hospital; 🇩🇰 Hvidovre, Denmark

Odense University Hospital; 🇩🇰 Odense, Denmark