Bone forming agents in the treatment of osteoporosis: to lump them or to split them ?

Bone-forming agents for very high risk

Bone-forming agents are first-line therapy in patients at high or very high fracture risk because they act faster and more strongly than antiresorptives and reduce fractures at all skeletal sites more than oral bisphosphonates.

Abaloparatide differs from teriparatide

Abaloparatide and teriparatide are not identical: abaloparatide shows a wider anabolic window, greater hip BMD and cortical volumetric BMD gains, and greater fracture reduction than teriparatide in cited trial, real-world, and network meta-analysis data.

Sequential therapy remains essential

All bone-forming agents require sequential treatment with an antiresorptive to maintain benefit after discontinuation; after prior potent antiresorptive therapy, romosozumab shows quicker hip BMD benefit than teriparatide, while fracture differences versus PTH receptor agonists are not demonstrated.

The continuing education activity “Bone forming agents in the treatment of osteoporosis: to lump them or to split them?” is organized by Klinik Barmelweid and presented by MD, PhD, MPH Jean Yves Reginster. Dr. Reginster describes the shift from a “one size fits all” approach with oral bisphosphonates toward risk-adapted treatment, emphasizing that patients at high or very high fracture risk should receive a bone-forming agent because these therapies act more rapidly and more strongly. He reviews the currently available bone-forming agents—PTH receptor agonists (teriparatide and abaloparatide) and the anti-sclerostin antibody romosozumab—and explains their distinct mechanisms of action on bone remodeling and modeling. Based on the data presented, abaloparatide shows a greater anabolic window, larger gains in hip and cortical volumetric BMD, and greater antifracture efficacy than teriparatide, whereas no current evidence demonstrates a difference in fracture reduction between PTH receptor agonists and romosozumab. The lecture further stresses that all bone-forming therapies should be used sequentially and followed by an antiresorptive agent to preserve or augment treatment benefit after discontinuation. In patients previously treated with potent antiresorptives, Dr. Reginster notes a blunted initial BMD response, particularly with teriparatide, while romosozumab appears to retain a quicker hip BMD benefit, although fracture implications remain uncertain. Regarding safety, he states that bone-forming agents are generally safe, including from a cardiovascular perspective, provided regulatory precautions for romosozumab are respected, and he notes that evidence in glucocorticoid-induced osteoporosis remains limited, especially for abaloparatide and romosozumab.