Osteoporosis
Decreased bone density and deterioration of bone structure leading to increased fracture risk. Peptide treatments include anabolic agents (teriparatide, abaloparatide) that build new bone, and calcitonin-salmon that inhibits bone resorption. Approximately 200 million people are affected worldwide.
Technical Context
Diagnosis: DEXA T-score ≤-2.5 at lumbar spine, femoral neck, or total hip. FRAX tool integrates BMD with clinical risk factors (age, sex, BMI, prior fracture, family history, smoking, alcohol, glucocorticoid use, RA, secondary osteoporosis) to calculate 10-year fracture probability. Treatment decision: FRAX-based thresholds (country-specific) or history of fragility fracture. Drug classes: anti-resorptive (bisphosphonates — first-line; denosumab — RANKL antibody) and anabolic/bone-forming (teriparatide — PTH 1-34, daily SC, 2-year limit due to osteosarcoma signal in rats; abaloparatide — PTHrP analogue, daily SC, potentially better balance of formation/resorption; palopegteriparatide — TransCon PTH, potential for different PK profile). Anabolic agents are generally reserved for severe osteoporosis (very low T-score, multiple fractures, or anti-resorptive failure). Sequential therapy strategy: anabolic first → transition to anti-resorptive (maintains bone gains) is more effective than anti-resorptive first.