What is the recommended treatment approach for a 67-year-old female patient with severe osteoporosis, previously treated with Evenity (romosozumab) and currently on Forteo (teriparatide), with frequent oral prednisone use for asthma?

Treatment Recommendations for Severe Osteoporosis with Glucocorticoid Use

Continuing Forteo (teriparatide) is the most appropriate treatment for this 67-year-old female with severe osteoporosis who has frequent prednisone use for asthma flares, as it is specifically indicated for glucocorticoid-induced osteoporosis and has demonstrated efficacy in high-risk patients.

Current Status Assessment

The patient presents with:

• Severe osteoporosis (T-score -3.0 in left femoral neck)
• Frequent oral prednisone use for asthma (a major risk factor)
• Previous treatment with Evenity (romosozumab) from Sept 2023-June 2024
• Currently on Forteo (teriparatide) since January 2025
• Some improvement in bone density from April 2023 to May 2025

Treatment Algorithm

1. Continue Anabolic Therapy

• Maintain current Forteo (teriparatide) treatment
  • Teriparatide is specifically indicated for glucocorticoid-induced osteoporosis 1
  • For patients with very severe osteoporosis (T-score ≤ -3.0), anabolic agents like teriparatide are preferred over antiresorptive agents 1
  • Teriparatide has demonstrated efficacy in increasing BMD in patients with glucocorticoid-induced osteoporosis 2

2. Treatment Duration

• Complete a full course of teriparatide (up to 24 months total)
  • FDA-approved duration is 24 months 2
  • Extended PTH analog therapy beyond 2 years should only be considered in exceptional cases 3

3. Plan for Sequential Therapy

• After completing teriparatide course, transition to an antiresorptive agent
  • Sequential therapy with an antiresorptive is strongly recommended after completing PTH analog therapy 3
  • Without antiresorptive follow-up, bone gains may be lost 4
  • Options include:
    • Alendronate or risedronate (first-line oral bisphosphonates) 1
    • Zoledronic acid (IV option if oral intolerance) 1
    • Denosumab (subcutaneous option) 1

4. Supplementation and Lifestyle Modifications

• Ensure adequate calcium and vitamin D intake:
  • Calcium: 1,200 mg daily 1
  • Vitamin D: 800 IU daily 1
  • Monitor serum vitamin D levels to maintain 25(OH)D ≥30 ng/mL 3
• Implement lifestyle modifications:
  • Weight-bearing and resistance exercises 3
  • Smoking cessation if applicable 1
  • Limit alcohol intake 1
  • Fall prevention strategies 3

Rationale for Continuing Teriparatide

1. Severe osteoporosis with glucocorticoid use: The patient has a T-score of -3.0 in the left femoral neck and frequent prednisone use, placing her at very high fracture risk 1.

2. Anabolic vs. antiresorptive therapy: For patients with very high fracture risk, anabolic agents like teriparatide are conditionally recommended over antiresorptive agents 1.

3. Evidence of efficacy: Teriparatide has demonstrated a 7.2% increase in lumbar spine BMD and 3.7% increase in femoral neck BMD in patients with glucocorticoid-induced osteoporosis 2.

4. Improvement already observed: The patient shows some improvement in bone density since starting treatment (left femoral neck T-score improved from -3.10 to -3.0).

Monitoring Recommendations

• BMD testing with DEXA after completing the full course of teriparatide
• Consider vertebral fracture assessment (VFA) or spinal X-rays to evaluate for asymptomatic vertebral fractures
• Monitor for adverse effects of teriparatide:
  • Hypercalcemia (nausea, vomiting, constipation, lethargy) 2
  • Orthostatic hypotension 2
  • Urolithiasis in patients with pre-existing hypercalciuria 2

Common Pitfalls to Avoid

1. Premature discontinuation: Stopping teriparatide before completing the full course can result in suboptimal bone formation.

2. Failure to transition to antiresorptive therapy: After teriparatide, patients must transition to an antiresorptive agent to maintain bone gains 4.

3. Concurrent bisphosphonate use: Avoid using bisphosphonates concurrently with teriparatide as this may blunt the anabolic response 3.

4. Inadequate calcium/vitamin D: Ensure adequate supplementation to support bone formation during teriparatide treatment 1.

5. Ignoring glucocorticoid minimization: Work with the patient's pulmonologist to minimize prednisone use for asthma when possible, using steroid-sparing strategies.