Should a different treatment for osteoporosis be started after completing Forteo (teriparatide)?

Sequential Therapy After Teriparatide (Forteo) for Osteoporosis

An antiresorptive medication should be started immediately after completing teriparatide (Forteo) therapy to maintain bone density gains and prevent bone loss. 1

Rationale for Sequential Therapy

• Teriparatide is an anabolic (bone-forming) agent that increases bone mineral density (BMD) and reduces fracture risk, but these benefits gradually diminish after discontinuation 2, 3
• Significant bone loss may occur after discontinuation of teriparatide, although anti-fracture efficacy may persist for up to 18 months 1
• Sequential therapy with an antiresorptive agent is strongly recommended to preserve the bone mass gained during teriparatide treatment 1

Recommended Sequential Treatment Options

First-line options:

• Oral bisphosphonates (alendronate, risedronate) are recommended as the first choice for sequential therapy after teriparatide due to their efficacy, safety profile, and cost-effectiveness 1
• Intravenous bisphosphonates (zoledronic acid) are appropriate alternatives if oral administration is contraindicated or if adherence is a concern 1

Second-line options:

• Denosumab (RANK ligand inhibitor) is an effective second-line option if bisphosphonates are contraindicated 1
• Note: If denosumab is used after teriparatide, it must eventually be followed by a bisphosphonate when discontinuing denosumab to prevent rapid bone loss 1

Treatment Algorithm Based on Patient Risk

For patients with low fracture risk after teriparatide:

• Start oral bisphosphonate therapy immediately after completing teriparatide 1
• Continue calcium (1,000-1,200 mg/day) and vitamin D (600-800 IU/day) supplementation 1

For patients who remain at high or very high risk of fracture:

• Consider more potent antiresorptive options such as intravenous bisphosphonates or denosumab 1
• For patients with BMD T-score < -2.5 or fragility fracture occurring after ≥12 months of osteoporosis therapy, continue with sequential therapy as recommended above 1

Timing and Duration of Sequential Therapy

• Begin antiresorptive therapy immediately after completing the 24-month course of teriparatide to prevent bone loss 3
• The optimal duration of sequential therapy is not clearly established, but treatment for at least 1 year with an oral bisphosphonate or 1-2 years with IV bisphosphonate is recommended 1
• Long-term bisphosphonate therapy should be reassessed after 3-5 years due to potential risks of rare adverse events 1

Important Considerations and Caveats

• Teriparatide should be limited to a single 24-month course of therapy due to regulatory restrictions and safety concerns 4, 3
• Prior treatment with bisphosphonates may blunt the anabolic response to subsequent teriparatide therapy, but the reverse sequence (teriparatide followed by bisphosphonate) is optimal 5, 6
• Sequential therapy with an antiresorptive agent after teriparatide provides better long-term fracture prevention than either agent alone 5, 6
• Combination therapy (simultaneous use of teriparatide and antiresorptive agents) is not generally recommended based on current evidence 3

Monitoring Recommendations

• Bone mineral density testing via DEXA scan should be performed to assess treatment response 1
• Biochemical markers of bone turnover may be used to assess adherence to antiresorptive therapy 1
• Regular assessment of calcium and vitamin D status is recommended 1