Journal of Osteoporosis and Physical Activity
Open Access

Romosozumab Outperforms Teriparatide in Building Bone Density

Arendt Bachmann^{* *}Correspondence: Arendt Bachmann, Department of Internal Medicine, The Johannes Gutenberg University Mainz, Mainz, Germany, Email:

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Description

Osteoporosis is a common and debilitating condition characterized by weakened bones and an increased risk of fractures. As life expectancy continues to rise, so does the prevalence of osteoporosis, particularly in postmenopausal women. For decades, healthcare providers have used various treatments to slow bone loss and even stimulate bone formation, including drugs like teriparatide and, more recently, romosozumab. Emerging research suggests that romosozumab, a newer option, is more effective at boosting bone density than teriparatide, which has long been a gold standard in osteoporosis treatment. Osteoporosis causes bones to become porous and fragile, often leading to fractures in the hip, spine, and wrists. These fractures can significantly reduce quality of life, lead to chronic pain, and increase mortality. Therefore, treatment strategies aim to increase Bone Mineral Density (BMD) and reduce fracture risk. Several medications are available, but they work through different mechanisms, either by slowing down bone resorption (the breakdown of bone tissue) or by promoting bone formation.

Teriparatide approach to bone formation

Teriparatide is a synthetic form of Parathyroid Hormone (PTH), which stimulates bone formation by promoting the activity of osteoblasts, the cells responsible for building new bone. Approved by the FDA in 2002, teriparatide has been widely used as an anabolic (bone-building) treatment, especially for individuals with severe osteoporosis or those who have not responded well to other treatments. Clinical studies have shown that teriparatide can significantly improve BMD, particularly in the spine, where it offers a notable reduction in vertebral fractures. However, teriparatide also has limitations. While it is effective in increasing BMD, its benefits plateau over time. After two years of continuous use, patients typically need to switch to another therapy, usually a bisphosphonate or other antiresorptive medication, to maintain the gains in bone density. Moreover, it is administered via daily injections, which can be cumbersome for patients.

Romosozumab as a care of osteoporosis

Romosozumab, approved by the FDA in 2019, represents a significant advancement in osteoporosis treatment. It is a monoclonal antibody that works by inhibiting sclerostin, a protein that inhibits bone formation. By blocking sclerostin, romosozumab not only promotes new bone formation but also reduces bone resorption, making it a dual-action treatment. This unique mechanism distinguishes romosozumab from other osteoporosis therapies, including teriparatide. Clinical trials have shown that romosozumab leads to greater increases in BMD compared to teriparatide. In a head-to-head study, known as the STRUCTURE trial, researchers compared the effects of romosozumab and teriparatide in postmenopausal women with osteoporosis who had previously been treated with bisphosphonates. After 12 months, women receiving romosozumab experienced a 9.8% increase in BMD at the lumbar spine, compared to a 5.4% increase in the teriparatide group. Similar trends were observed in the hip, where romosozumab increased BMD by 3.2%, compared to a 0.9% increase with teriparatide. These results are particularly significant because increases in BMD are closely correlated with a reduction in fracture risk. Since fractures in the spine and hip are the most devastating for osteoporosis patients, the superior bonebuilding effects of romosozumab are expected to translate into better outcomes for patients.

Advantages of romosozumab over teriparatide

Romosozumab dual mechanism of action is one of its major advantages. While teriparatide primarily builds new bone, romosozumab both stimulates bone formation and reduces bone breakdown, offering a more comprehensive approach to treating osteoporosis. Additionally, romosozumab is administered via a monthly injection, compared to teriparatide daily injection regimen, making it more convenient for patients and potentially improving adherence to treatment. Furthermore, romosozumab has demonstrated a faster and more robust increase in bone density than teriparatide, which could be important for patients at high risk of fractures. The structure trial also showed that romosozumab was more effective in increasing cortical bone thickness, which is important for preventing fractures in areas like the hip and other long bones. While romosozumab offers significant advantages, it is not without risks. The FDA has issued a warning regarding potential cardiovascular side effects, such as heart attacks and strokes, associated with romosozumab. As a result, it is not recommended for patients with a history of cardiovascular disease. Teriparatide, on the other hand, does not carry this risk, but its long-term use is limited due to concerns about the potential risk of osteosarcoma (a rare type of bone cancer) seen in animal studies, although this has not been observed in humans.

Conclusion

The advent of romosozumab marks a significant advancement in the treatment of osteoporosis, offering a superior ability to increase bone density compared to teriparatide. Its dual-action mechanism, coupled with more convenient dosing, makes it an attractive option for patients at high risk of fractures. However, its cardiovascular risks mean that careful patient selection is important. For individuals without cardiovascular risk factors, romosozumab may represent the best available option for maximizing bone strength and minimizing fracture risk.