What is the recommended treatment regimen for Forteo (teriparatide) in patients with osteoporosis?

Teriparatide (Forteo) Treatment Regimen for Osteoporosis

Teriparatide should be administered at a dose of 20 mcg subcutaneously once daily for up to 24 months, followed by bisphosphonate therapy to maintain bone density gains. 1, 2

Patient Selection

• Teriparatide is indicated for patients at high risk for fracture, including:

  • Postmenopausal women with osteoporosis 1, 3, 2
  • Men with primary or hypogonadal osteoporosis 2
  • Men and women with osteoporosis associated with sustained systemic glucocorticoid therapy 2
  • Patients who have failed or are intolerant to other available osteoporosis therapy 1, 3, 2

• "Very high risk" patients who would benefit most from teriparatide include those with:

  • Older age (typically >74 years) 1, 3
  • Recent fracture (within past 12 months) 1, 3
  • History of multiple clinical osteoporotic fractures 1, 3
  • Multiple risk factors for fracture 1, 3
  • Failure of other available osteoporosis therapies 1, 3

Administration Protocol

• Administer 20 mcg subcutaneously once daily into the thigh or abdominal region 2
• Initial administration should occur under circumstances where the patient can sit or lie down if orthostatic hypotension occurs 2
• Consider calcium and vitamin D supplementation based on individual patient needs 2
• Treatment duration should be limited to 24 months during a patient's lifetime 2, 4
• Extended use beyond 24 months should only be considered if a patient remains at or has returned to having a high risk for fracture 2

Efficacy

• Teriparatide reduces the risk of:

  • Any clinical fractures (27 fewer events per 1000 patients; high certainty) 1, 3
  • Radiographic vertebral fractures (69 fewer events per 1000 patients; high certainty) 1, 3
  • Clinical vertebral fractures (45 fewer events per 1000 patients; low certainty) 1
  • Nonvertebral fractures in postmenopausal women 5

• Compared to bisphosphonates, teriparatide:

  • Reduces radiographic vertebral fractures (66 fewer events per 1000 patients; moderate certainty) 1, 3
  • May reduce any clinical fracture (46 fewer events per 1000 patients; low certainty) 1, 3
  • May not significantly reduce risk for hip fractures (low certainty evidence) 3

Post-Treatment Protocol

• After completing teriparatide therapy, patients should transition to bisphosphonate therapy to maintain bone density gains 1, 3, 4
• Discontinuation without follow-up antiresorptive therapy results in rapid bone loss 1, 6

Important Precautions

• Avoid use in patients with increased risk of osteosarcoma including:

  • Patients with open epiphyses 2
  • Metabolic bone diseases including Paget's disease 2
  • Bone metastases or history of skeletal malignancies 2
  • Prior external beam or implant radiation therapy involving the skeleton 2
  • Hereditary disorders predisposing to osteosarcoma 2

• Monitor for potential adverse effects:

  • Hypercalcemia and cutaneous calcification 2
  • Urolithiasis in patients with active or recent history 2
  • Orthostatic hypotension, particularly with initial doses 2
  • Common adverse reactions (>10%) include arthralgia, pain, and nausea 2, 7

• Consider drug interactions:

  • Transient hypercalcemia may predispose patients to digitalis toxicity 2