What is the recommended dose of teriparatide (Fortéo) for an adult patient with osteoporosis, including those with impaired renal function?

Teriparatide Dosing for Osteoporosis

Standard Dose

The recommended dose of teriparatide is 20 mcg administered subcutaneously once daily into the thigh or abdominal region. 1, 2, 3

• This dose is standard for all adult patients with osteoporosis, regardless of sex 3
• Administration should occur at approximately the same time each day 3
• Treatment duration is limited to a maximum of 2 years during a patient's lifetime, unless the patient remains at or returns to very high fracture risk 1, 2

Dosing in Renal Impairment

No dose adjustment is required for patients with mild to moderate renal impairment (creatinine clearance ≥30 mL/min). 3

• Pharmacokinetic studies showed no significant differences in patients with creatinine clearance 30-72 mL/minute 3
• In severe renal impairment (CrCl <30 mL/min), the standard 20 mcg dose can still be used, but with awareness that drug exposure increases by approximately 73%. 3
• The elimination half-life increases from approximately 0.79 hours to 1.4 hours in severe renal impairment, but the drug is still eliminated within 24 hours, making accumulation unlikely with once-daily dosing 3, 4
• No studies have been performed in dialysis patients 3

Required Supplementation

All patients on teriparatide must receive concurrent calcium and vitamin D supplementation. 1, 5, 2

• Calcium: 1,000-1,200 mg daily 1, 5, 2
• Vitamin D: 600-800 IU daily, targeting serum levels ≥20 ng/mL 1, 2

Pharmacokinetic Profile

The drug demonstrates rapid absorption and elimination characteristics that support once-daily dosing 3, 6:

• Peak serum concentration (Tmax): 0.25 hours (median 15 minutes) 3
• Maximum concentration (Cmax): 109.5 pg/mL 3
• Elimination half-life: 0.79 hours 3
• Drug becomes non-quantifiable within 3 hours after injection 3
• Serum calcium peaks at approximately 4.25 hours post-dose with a median increase of 0.4 mg/dL, returning to baseline by 16-24 hours 6

Critical Dosing Considerations

Teriparatide should never be used as first-line therapy—bisphosphonates remain the initial treatment for most patients due to significantly lower cost. 1, 5

• Reserve teriparatide for patients at very high fracture risk (T-score ≤-3.5, multiple prevalent fractures, or fractures occurring on therapy) 5
• Use only in patients who have failed or cannot tolerate bisphosphonates 1, 5, 7
• Following completion of teriparatide therapy, transition to antiresorptive therapy (bisphosphonate or denosumab) to preserve bone mass gains 1
• Do not combine with bisphosphonates during active treatment—teriparatide is best given as monotherapy 1

Absolute Contraindications to Any Dose

Do not use teriparatide in patients with 5, 2:

• Bone metastases or history of skeletal malignancies 5
• Prior external beam or implant radiation therapy involving the skeleton 5
• Open epiphyses 5
• Paget's disease of bone 5