What is Forsteo?
Forsteo is a pre-filled pen containing a solution for injection. Forsteo contains the active substance teriparatide (a 2.4 ml pre-filled pen contains 600 micrograms of teriparatide).
What is Forsteo used for?
Forsteo is used to treat osteoporosis (a disease that makes bones fragile) in the following groups:
- postmenopausal women. In these patients Forsteo has been shown to significantly reduce vertebral (spine) fractures and non-vertebral fractures (broken bones), but not those of the hip;
- men with increased risk of fractures;
- men and women with increased risk of fractures due to long-term treatment with glucocorticoids (a type of steroid).
The medicine can only be obtained with a prescription.
How is Forsteo used?
The recommended dose of Forsteo is 20 micrograms administered once a day by subcutaneous injection (under the skin) in the thigh or abdomen (belly). The patient can practice the injection alone after training. For the pen, a user manual is available.
Generally calcium and vitamin D supplements are recommended in women with reduced dietary calcium intake. Forsteo can be used for a maximum of two years. It should only be taken for a two-year cycle throughout a patient's life. Forsteo should not be used in children or young people with a bone structure that is not yet fully mature.
How does Forsteo work?
Osteoporosis occurs when there is no new bone sufficient to replace what is naturally consumed. The bones become progressively thin and fragile and more prone to fracture. Osteoporosis becomes more common in postmenopausal women, when female estrogen hormone levels decrease. Osteoporosis can also occur in both sexes as a side effect of glucocorticoid treatment.
Teriparatide, the active ingredient in Forsteo, is identical to a part of the human parathyroid hormone. Similarly to the human hormone, Forsteo stimulates bone formation by acting on osteoblasts
(cells responsible for bone formation). Furthermore, this substance increases the absorption of calcium present in food and prevents it from being over-dispersed by urine.
Teriparatide is produced by a method known as "recombinant DNA technology": this hormone is obtained starting from a bacterium in which a gene (DNA) has been introduced that makes it capable of producing the hormone. Forsteo replaces the natural hormone.
What studies have been carried out on Forsteo?
Forsteo has been studied in three main studies. The first study involved 1, 637 women with postmenopausal osteoporosis (average age: 69.5 years), in which Forsteo was compared with a placebo (a dummy treatment) for an average duration of 19 months. The main efficacy index was based on the number of new vertebral fractures at the end of the study, although this also took into account non-vertebral fractures. Patients were treated for up to 23 months.
The second study examined the use of Forsteo in 437 men with osteoporosis, comparing their effects on bone density in the spine compared to a placebo treatment.
Finally, the third study compared the effects of Forsteo and alendronate (another medicine used to treat osteoporosis) on the bone density of the spine for over three years. The study included 429 women and men who had osteoporosis and had been on glucocorticoids for at least three months.
A further study examined the effects of Forsteo on bone density in 234 post-menopausal women for two years.
What benefit has Forsteo shown during the studies?
Forsteo was more effective than placebo in reducing vertebral fractures. 5% of women treated with Forsteo suffered a new fracture during the study, compared with 14% of the placebo group. During the 19-month study duration, Forsteo reduced the risk of a new vertebral fracture by 65% compared to placebo. The medicine also reduced the risk of non-vertebral fractures by 62%, but not that of hip fractures.
In the study on men, Forsteo increased bone density in the spine by about 6% after an average period of almost 12 months.
In the study of patients taking glucocorticoids, Forsteo was more effective than alendronate: after 18 months, patients treated with Forsteo reported a 7% increase in bone density in the spine, compared to 3% of those treated with alendronate .
These studies also showed that the benefits of Forsteo treatment continued to increase for up to two years, with a further increase in bone density.
What is the risk associated with Forsteo?
The most common adverse reaction seen with Forsteo (in more than 1 patient in 10) is pain in the arms or legs. For the full list of all side effects reported with Forsteo, see the Package Leaflet.
Forsteo should not be used in people who may be hypersensitive (allergic) to teriparatide or any of the other substances. It must not be used in patients suffering from other bone dysfunctions such as Paget's disease, bone cancer or bone metastases (cancer that has spread to the bones), or in patients who have had skeletal radiotherapy, or who have hypercalcaemia ( high levels of calcium in the blood), with unexplainedly high levels of alkaline phosphatase (an enzyme) or with severe kidney disease. Forsteo should not be used in children or young people with a bone structure that is not yet fully mature, or during pregnancy or lactation.
Why has Forsteo been approved?
The Committee for Medicinal Products for Human Use (CHMP) concluded that Forsteo's benefits are greater than its risks for the treatment of osteoporosis in post-menopausal women and in men with an increased risk of fractures, as well as for the treatment of osteoporosis in association with systemic treatment supported with glucocorticoids in women and men with an increased risk of fractures. The Committee recommended that Forsteo be given marketing authorization.
More information on Forsteo
On 10 June 2003, the European Commission granted Forsteo a marketing authorization valid throughout the European Union to Eli Lilly Nederland BV. The marketing authorization was renewed on 10 June 2008.
For the full EPOR for Forsteo, click here.
Last update of this summary: 02-2009.
