Teriparatide
parathyroid hormone analogue · severe osteoporosis
Third-party optionBy the Layer Nutrition editorial team · How the atlas classifies the 664 molecules
What this medicine is for
Teriparatide belongs to the “parathyroid hormone analogue (severe osteoporosis)” category. This medicine strengthens the bone and reduces the risk of fracture.
For Teriparatide, in practice: Stimulates bone formation in severe osteoporosis. It is generally taken over the long term, within regular monitoring, and is not stopped on your own initiative.
Under which brands it is found
In France, about 7 reimbursable presentations containing Teriparatide are recorded. It is found under several brand names and as generics.
- Forsteo
- Livogiva
- Movymia
- Sondelbay
- Teriparatide Biogaran
- Teriparatide Teva
- Terrosa
Original brand-name products and generics deliver the same active substance; the choice between them is made with your doctor or pharmacist.
On the plate: calcium and vitamin D
Teriparatide builds new bone, and that bone needs raw material. The clinical trials were all conducted with a daily intake of calcium and vitamin D. Calcium comes largely from food; vitamin D is mostly formed in the skin under the action of sunlight, and food covers only part of it.
Calcium comes first from dairy products such as milk and cheese, from leafy green vegetables such as kale, and from small fish eaten with their bones such as sardines. The calcium in spinach is poorly absorbed, which makes it an unreliable source despite its reputation.
Vitamin D is concentrated in oily fish: salmon, sardines, mackerel, herring. Red meat, liver and egg yolks also provide some. Bringing these foods together over the week covers part of the requirement, in addition to your treatment.
How teriparatide works
Teriparatide is a recombinant fragment of human parathyroid hormone, its active 1-34 portion. It binds to the type 1 PTH receptor, the PTH1R, a G protein-coupled receptor present on the surface of osteoblasts, osteocytes and kidney cells. By binding to it, it activates the Gs and Gq signalling pathways inside the cell, which trigger the bone response.
Its effect depends above all on the rhythm of administration. A single injection per day, at a low dose, stimulates bone formation more than its breakdown. This is the opposite of continuous exposure to parathyroid hormone, as in hyperparathyroidism, which instead promotes bone resorption. At the molecular level, teriparatide increases pro-osteoblastic factors such as IGF-1 and FGF2, releases the brake that sclerostin places on the Wnt/beta-catenin pathway, and raises the transcription factor Runx2, which directs cells towards the osteoblast lineage.
Why teriparatide is prescribed
Teriparatide is aimed at severe forms of osteoporosis, when the risk of fracture is high. It is indicated in postmenopausal women at high risk of fracture, in men with primary osteoporosis or osteoporosis linked to a hormone deficiency, and in osteoporosis caused by corticosteroids. The label describes stimulation of new bone formation on trabecular and cortical surfaces, through a preferential action on osteoblasts rather than on osteoclasts.
This rebuilding translates into fewer fractures. In the pivotal trial in postmenopausal women, the risk of a new vertebral fracture fell from 14.3% on placebo to 5.0% on teriparatide, a relative reduction of about 65%. The risk of a new non-vertebral fragility fracture dropped from 5.5% to 2.6%, a relative reduction of about 53%.
How to take it day to day
The recommended dose is 20 micrograms per day, in a single subcutaneous injection. It is given in the thigh or the abdominal wall, each day at a regular time. The serum half-life after injection is about one hour: the product passes through quickly, and it is precisely this brief, repeated passage that carries the anabolic effect. Regularity of dosing therefore matters more than the exact time.
The first injections are given sitting or lying down, because a drop in blood pressure when standing up, orthostatic hypotension, can occur. Treatment is not stopped on one's own initiative, because its benefit rests on continuity. Its duration is limited: beyond two years over a patient's lifetime, it is only renewed if the risk of fracture remains or becomes high again.
The effects to know about
Most of the reported effects remain close to what the placebo group experiences. Out of 691 patients per arm at the 20 microgram dose, pain was recorded in 21.3% (versus 20.5%), joint pain in 10.1% (versus 8.4%), nausea in 8.5% (versus 6.7%), dizziness in 8.0% (versus 5.4%), and fatigue in 8.7% (versus 6.8%). Two effects stand out a little more: leg cramps, 2.6% versus 1.3%, and syncope, 2.6% versus 1.4%.
The most characteristic biological effect is a transient rise in blood calcium, in the four to six hours after the injection. It affected 11% of treated women and 6% of treated men, versus 2% and 0% on placebo. This hypercalcaemia is most often mild and transient, and becomes persistent only in about 3% of patients at 20 micrograms per day. Teriparatide also raises blood uric acid: 3% of patients exceeded the upper limit of normal versus 1% on placebo, without any increase in cases of gout, joint pain or urinary stones.
Calcium, vitamin D and blood calcium
The bone that teriparatide makes needs calcium and vitamin D to mineralise. In the trials, all women received 1000 mg of calcium and at least 400 IU of vitamin D each day, and this sufficient intake is recommended throughout treatment. Teriparatide increases urinary calcium excretion, but the frequency of hypercalciuria seen in the trials remained comparable to that of placebo. For phosphorus, single-dose studies show a transient urinary elimination and a mild, transient fall in the blood level, without any hypophosphataemia appearing in the clinical trials.
Calcium intake is managed according to blood calcium. If it rises during treatment, the approach is first to reduce the calcium provided by supplements before adjusting the teriparatide dose. Food remains the simplest way to regularly provide the calcium that bone needs, with vitamin D also coming from sun exposure.
Interactions and monitoring
One interaction calls for particular attention: in patients treated with digoxin, the transient rise in blood calcium can promote toxicity of this heart medicine, whose signs must be monitored. Biological monitoring of teriparatide includes a measurement of blood and urinary calcium before starting, a control blood calcium at one month and then according to clinical judgement, a measurement of bone mineral density at one year, and the possibility of following bone remodelling markers such as P1NP.
On long-term safety, an increased incidence of osteosarcoma was observed in treated rats, but this excess risk was not found in observational studies in humans, and data beyond two years of use remain limited. This is the reason why the duration of treatment is framed and its continuation reassessed according to the risk of fracture.
Sources
Related molecules
To explore within the « Bones and joints » family and its neighbours.
See the entire « Bones and joints » family · Back to the atlas
Supplements to consider
Beyond the plate, a single isolated nutrient can be worth discussing, to confirm with your doctor or pharmacist. Here is which one and in which form.
Calcium
Calcium is the most abundant mineral in the body, involved in bone health. Calcium citrate is well absorbed, including away from meals, whereas carbonate requires an acidic environment for its absorption.
Preferred form calcium citrate (does not depend on gastric acidity)
Vitamin D3 (cholecalciferol)
Vitamin D is a fat-soluble vitamin. The D3 form (cholecalciferol) is the one adopted by most guidelines. It is better absorbed when taken during a meal that contains fats.
Preferred form D3 (cholecalciferol), during a fatty meal
Frequently asked questions
What are the side effects of teriparatide?
The leaflet notably mentions nausea, pain in the limbs, headaches, dizziness and, more rarely, a transient rise in blood calcium. For the full list and the warning signs to watch for, refer to your medication's leaflet and speak with your doctor or pharmacist.
Does teriparatide interact with other medications?
The leaflet flags particular caution with digitalis medicines such as digoxin, because a change in calcium levels can alter their effect. Report all your treatments to your doctor or pharmacist and follow the recommendations in the leaflet.
How long does teriparatide treatment last and what happens when you stop?
The duration of treatment is limited in time and set by your doctor; afterwards, a switch to another osteoporosis treatment is often considered. What to do in case of a missed dose or discontinuation is set out in the leaflet and is decided with your doctor.
Is teriparatide safe during pregnancy or breastfeeding?
The leaflet states that teriparatide must not be used during pregnancy or breastfeeding. If you are affected or are planning a pregnancy, speak with your doctor before making any decision.
Should you monitor your calcium and vitamin D intake while taking teriparatide?
Health authorities recommend adequate calcium and vitamin D intake during osteoporosis treatment, as these two nutrients are needed for bone mineralization. Vitamin D status is checked with a blood test; discuss monitoring and possible supplementation with your doctor.
Which forms of calcium and vitamin D are best to take?
For vitamin D, the best-documented form is cholecalciferol (vitamin D3). For calcium, calcium citrate and calcium carbonate are the usual forms, with carbonate preferably taken with a meal. Whether a supplement is worthwhile, and which one, is decided with your doctor based on your dietary intake and your test results.
Ces réponses portent sur le volet nutritionnel. Pour toute question sur votre médicament, la notice et votre médecin ou pharmacien font foi.