PTH Analog Therapy in CKD G4-G5D: Current Evidence and Potential Role of Abaloparatide in Adynamic Bone Disease.

Osteoporosis and fragility fractures are among the most prevalent and clinically significant complications in patients with chronic kidney disease (CKD), particularly in stages G4-G5 and in those undergoing dialysis (G5D). These skeletal disorders are associated with markedly increased morbidity and mortality, including a 2- to 9-fold higher risk of hip fractures compared to the general population, prolonged hospitalization, functional decline, and excess postoperative mortality. Despite this substantial burden, CKD-associated osteoporosis remains underrecognized and undertreated. Limited inclusion of CKD patients in pivotal osteoporosis trials and the absence of high-evidence guidance in clinical guidelines have contributed to a persistent therapeutic gap. PTH analog agents such as teriparatide and abaloparatide have demonstrated robust efficacy in increasing bone mass and reducing fracture risk in the general population. However, their use in CKD remains limited. PTH analog are poorly prescribed in patients with CKD stage G3 and remain off-label for stages G4-G5D, despite the high prevalence of adynamic bone disease across all stages of CKD. Abaloparatide, a selective PTH1 receptor agonist, exerts potent anabolic effects with a lower incidence of hypercalcemia than teriparatide and may offer a favourable safety profile in carefully selected patients. Preliminary data suggest preservation of bone microarchitecture and potential benefits in low-turnover bone disease, although evidence in CKD is still limited. This narrative review examines current evidence on abaloparatide's potential role in CKD, emphasizing its mechanism of action, efficacy, safety, and relevance for patients with low bone turnover and high fracture risk.