Should Prolia (denosumab) be discontinued and Evenity (romosozumab) started in a 70-year-old smoker with osteoporosis and a T score of -2.8 in the distal ulnar and radial bones?

Management of Osteoporosis in a 70-Year-Old Smoker with Distal Radius Osteoporosis

Prolia (denosumab) should be continued rather than switching to Evenity (romosozumab) in this 70-year-old smoker with osteoporosis who has shown improvement and stability in femoral neck, total hip, and lumbar spine BMD measurements on Prolia.

Assessment of Current Treatment Response

• The patient has demonstrated positive response to Prolia with:

  • Improved BMD at femoral neck, total hip, and lumbar spine between 2022-2024
  • Stable BMD at these sites in 2025
  • Only the newly measured distal ulnar and radial sites show a T-score of -2.8

• This pattern suggests that Prolia is effectively treating the central skeletal sites (spine and hip) which are most associated with serious fracture outcomes 1

Rationale for Continuing Prolia

1. Treatment is working at critical fracture sites:

   • Hip and spine are the most clinically significant sites for fracture risk assessment and treatment monitoring 1
   • Improvement and stabilization at these sites indicates successful treatment

2. Age and risk factors:

   • At 70 years of age with smoking history, the patient has significant risk factors for osteoporosis 1
   • Denosumab has shown efficacy in geriatric populations with no need for dose adjustment 2

3. Distal radius findings:

   • The distal radius T-score of -2.8 is newly measured and doesn't necessarily indicate treatment failure
   • According to ACR guidelines, the primary monitoring sites for osteoporosis treatment are the lumbar spine and hip 1

Concerns with Switching to Evenity

1. Cardiovascular risk:

   • Evenity carries a boxed warning for increased risk of major adverse cardiac events 3
   • This is particularly concerning in a 70-year-old smoker who likely has elevated baseline cardiovascular risk

2. Limited treatment duration:

   • Romosozumab is limited to a 12-month course 3, 4
   • Would require sequential therapy with an antiresorptive agent afterward 1, 5

3. Rebound concerns:

   • Switching from Prolia without appropriate sequential therapy can lead to rapid bone loss and increased vertebral fracture risk 1

Recommended Approach

1. Continue Prolia (denosumab):

   • Maintain current 6-month dosing schedule
   • Ensure adequate calcium and vitamin D supplementation 1

2. Address modifiable risk factors:

   • Strongly encourage smoking cessation as this is a significant risk factor for osteoporosis 1
   • Recommend weight-bearing exercise if not contraindicated

3. Monitoring plan:

   • Continue regular DXA scans to monitor BMD at central sites (hip and spine)
   • Consider vertebral fracture assessment (VFA) if not recently performed 1
   • Monitor for potential side effects of long-term denosumab therapy

Special Considerations

• If the patient were to discontinue Prolia in the future, a sequential therapy plan would be essential to prevent rebound bone loss 1
• If a fragility fracture occurs while on Prolia, or if BMD significantly decreases at central sites, then reassessment of therapy would be warranted 1

The evidence strongly supports continuing a medication that is showing effectiveness at the most clinically significant skeletal sites rather than switching to a medication with higher cardiovascular risk and limited treatment duration in this 70-year-old smoker.