Mechanisms of Anabolic Osteoporosis Therapy

This study investigates how romosozumab — an anabolic (bone-building) medication for osteoporosis — works at the cellular and tissue level. Postmenopausal women prescribed romosozumab by their own doctors will undergo bone marrow aspirates and biopsies at two timepoints to provide detailed biological data, helping researchers better understand how this drug rebuilds bone. You may be eligible if: - You are a postmenopausal woman aged 45 or older - Your doctor has already prescribed romosozumab for you based on the FDA-approved indication (high fracture risk osteoporosis) - You have been postmenopausal for more than 36 months (either by natural menopause, hysterectomy plus FSH testing, or other criteria) - You are not at increased risk for a bone marrow aspirate or biopsy You may NOT be eligible if: - You have stage 4 chronic kidney disease (CKD) - Your blood PTH is elevated (above 77 pg/mL) - Your vitamin D level is below 20 ng/mL - You have a major psychiatric disorder, severe alcohol use, or substance abuse that would impair your ability to participate - You have a known bone disease other than osteoporosis - You have taken oral bisphosphonates within the past 3 months, denosumab within 12 months, or IV bisphosphonates within 24 months - You have taken estrogens, SERMs, calcitonin, or glucocorticoids recently - You have previously received romosozumab Talk to your doctor to see if this trial is right for you.