Strategies for zoledronic acid post-denosumab discontinuation in postmenopausal osteoporosis

Prior treatment

• Ongoing treatment with systemic glucocorticoids. However, substitutive treatment with hydrocortisone (20-30 mg/per day) is tolerated.
• Daily systemic glucocorticoids ≥ 7.5 mg prednisone-equivalent used for at least 3 months, and stopped less than 3 months prior inclusion.
• Contra-indication to bisphosphonates according to license recommendation including: o Chronic kidney disease with Glomerular filtration rate stage > or = G3b (<35 mL/min) o Prior intolerance to zoledronic acid or another bisphosphonate o Hypocalcemia

Other illness

• Bone disease other than post-menopausal osteoporosis, including metabolic bone disease
• Uncontrolled endocrine diseases
• Liver failure
• Cancer not in remission for at least 5 years. Chronic asymptomatic hemopathies not requiring treatment are tolerated (e.g., asymptomatic Binet stage A chronic lymphocytic leukaemia, etc.)
• Use of medication affecting bone metabolism during the last year: bisphosphonates, teriparatide, romosozumab, hormone replacement therapy, selective Estrogen receptor modulators, breast cancer hormonotherapy

Other

• Subjects unable to give an informed consent or to fill the case report form
• Subjects under law protection
• Foreseeable poor compliance with the strategy, alcoholism, toxicomania.
• Patients with non-healed jaw injury

• Women aged ≥ 18 years
• With post-menopausal osteoporosis AND treated with denosumab for at least 2 years
• With post-menopausal osteoporosis - AND reaching decision of denosumab withdrawal because of achieved therapeutic target defined as no fracture during the last 2 years of treatment; no new risk factors; no BMD decrease > 0.03 g/cm² at the spine or hip
• With post-menopausal osteoporosis - AND with a history of severe fracture OR a femoral or a lumbar T-score ≤ −2.5 prior denosumab initiation.
• Free, informed and written consent signed by the participant and the investigator (at the latest on the day of inclusion and before any examination required by the research).
• Person affiliated or beneficiary of the French social security scheme.