What is the effect of Prolia (denosumab) treatment on improvement in Dual-Energy X-ray Absorptiometry (DEXA) scan results?

From the Guidelines

Prolia (denosumab) treatment is highly effective in improving bone mineral density (BMD) on DEXA scans, with most patients experiencing a 3-6% increase in BMD at the lumbar spine and 2-4% at the hip after one year of treatment, as supported by recent guidelines 1.

Key Points to Consider

• Prolia is administered as a 60mg subcutaneous injection every 6 months and works by inhibiting RANK ligand, which reduces osteoclast activity and bone resorption.
• For optimal results, patients should take calcium (1000-1200mg daily) and vitamin D (800-1000 IU daily) supplements alongside Prolia, as recommended by guidelines for the prevention and treatment of glucocorticoid-induced osteoporosis 1.
• DEXA scans are typically performed at baseline and then every 1-2 years to monitor treatment effectiveness, with the frequency of monitoring depending on the individual patient's risk factors and response to treatment 1.
• It's essential to maintain consistent treatment as discontinuing Prolia without transitioning to another therapy can lead to rapid bone loss and increased fracture risk, highlighting the importance of sequential OP treatment to prevent rebound bone loss and vertebral fractures after discontinuation of DEN, romosozumab, and PTH/PTHrP 1.

Important Considerations for Treatment

• Side effects may include low calcium levels, skin infections, and rarely, osteonecrosis of the jaw or atypical femur fractures, emphasizing the need for regular dental check-ups before and during treatment to minimize jaw-related complications.
• The American College of Rheumatology guidelines recommend that all adult patients with medium, high, or very high fracture risk should be offered OP therapy, with denosumab being conditionally recommended over antiresorptive agents in certain patient populations 1.
• The choice of treatment should be individualized based on the patient's specific risk factors, medical history, and preferences, with consideration given to the potential benefits and risks of each treatment option.

From the FDA Drug Label

1. 2 Pharmacodynamics In clinical studies, treatment with 60 mg of Prolia resulted in reduction in the bone resorption marker serum type 1 C-telopeptide (CTX) by approximately 85% by 3 days, with maximal reductions occurring by 1 month. Consistent with the physiological coupling of bone formation and resorption in skeletal remodeling, subsequent reductions in bone formation markers (i.e., osteocalcin and procollagen type 1 N-terminal peptide [P1NP]) were observed starting 1 month after the first dose of Prolia.

Improvement in DEXA scan with Prolia treatment is expected as the drug decreases bone resorption and increases bone mass and strength.

• The reduction in bone resorption markers and increase in bone mass suggest a positive effect on bone density, which can be measured by DEXA scan.
• However, the provided text does not directly mention the improvement in DEXA scan results. 2 2

From the Research

Prolia Treatment and Improvement in DEXA Scan

• Prolia (denosumab) is a human monoclonal antibody that targets the key bone resorption mediator RANKL, and is administered via subcutaneous injection once every 6 months 3.
• Studies have shown that denosumab increases bone mineral density (BMD) and reduces the risk of vertebral, nonvertebral, and hip fractures in postmenopausal women with osteoporosis 3, 4.
• A meta-analysis of randomized controlled trials found that denosumab improved BMD significantly more than bisphosphonate treatment at the lumbar spine, total hip, and femoral neck at 12 and 24 months 4.
• Another study found that sequential treatment with denosumab after bisphosphonate therapy improved lumbar spine BMD in postmenopausal osteoporosis patients 5.
• The use of denosumab in osteoporosis has been shown to be effective in improving BMD and reducing the incidence of new fractures, and may be an appropriate initial therapy in patients at high risk for fracture 6.
• Denosumab has been compared to bisphosphonates in several studies, and has been found to be more effective in improving BMD and reducing the risk of vertebral fractures in men with osteoporosis 7.

Key Findings

• Denosumab increases BMD and reduces the risk of fractures in postmenopausal women with osteoporosis 3, 4.
• Denosumab is more effective than bisphosphonates in improving BMD at the lumbar spine, total hip, and femoral neck 4.
• Sequential treatment with denosumab after bisphosphonate therapy improves lumbar spine BMD in postmenopausal osteoporosis patients 5.
• Denosumab may be an appropriate initial therapy in patients at high risk for fracture, including older patients and those who are intolerant of or unresponsive to other therapies 6.