Osteoporosis treatment bisphosphonates

Bisphosphonates are the cornerstone for osteoporosis treatment. They are the drugs of choice because they prevent both nonvertebral (especially hip) and vertebral fractures. 

Some patients cannot tolerate oral bisphosphonates. Zoledronic acid is not FDA-approved for osteoporosis treatment, but is sometimes administered intravenously once yearly in patients for whom bisphosphonates are indicated. It improved BMD similarly to oral bisphosphonates, but the impact on fracture rates is under investigation. Quarterly administration of intravenous pamidronate or ihandronate also improves BMD. 

Teriparatide contains the first 34 amino acids in human parathyroid hormone and represents a novel approach to osteoporosis treatment. Although hyperparathyroidism leads to bone loss (see Fig. 88-3), therapeutic doses (for shorter periods of time) conversely improve BMD and rednce fractnre risk. Parathyroid hormone is currently the only approved osteoporosis medication that works by stimulating bone formation. Becanse of adverse effects and cost concerns, teriparatide is reserved for treating those at high risk of osteoporosis-related fracture who cannot or will not take or have failed bisphosphonate therapy. 

Watts NB Treatment of osteoporosis with bisphosphonates. Rheum Dis Clin North Am 27(1) 197-214,... 

The goals of osteoporosis treatment are to control pain from the disease, reduce bone loss, and prevent bone fractures with medicines or hormone therapies. There are several types of treatments for osteoporosis including most famous bisphosphonates, estrogen agonists/antagonists, parathyroid... 

Very few marine compounds have been studied and reported for osteoporosis treatment. Still much research work is needed for further implications. Although S5mthetic bisphosphonates compoimds are more promising for osteoporosis treatment, marine algal extracts and their... 

Bisphosphonates have been shown to be highly effective in osteoporosis, cancer bone metastasis, multiple myeloma, and Paget s disease of bone. While generally very well tolerated, these drugs do have potential adverse effects. Recently, the association of long-term high dose bisphosphonate treatment with osteonecrosis of the jaw has been described. This is a potentially serious side effect seen mostly in patients with multiple myeloma or... 

The bisphosphonates are drags used to treat musculoskeletal disorders such as osteoporosis and Fhget s disease. This chapter will discuss the use of these drugs in the treatment of osteoporosis. 

The bisphosphonates are used to treat osteoporosis in postmenopausal women, Paget s disease of the bone, and postoperative treatment after total hip replacement (etidronate). 

These results indicated osteoporosis. In this condition, which often appears secondary to another pathology such as an endocrinopathy, chronic renal failure or following long term immobilization, bone architecture is normal hut its mass is reduced relative to its volume, that is there is normal mineralization hut the amount of osteoid matrix is reduced. Treatment is with bone resorption inhibitors such as the bisphosphonate group of drugs, for example alendronate. 

Bonviva consists of ibandronic acid, a bisphosphonate and is available as 150 mg tablets and 1 mg/mL injection. Patients receiving the oral formulation for the treatment of postmenopausal osteoporosis are advised to take one tablet once a month. Absorption of bisphosphonates from the gastrointestinal tract may be effected by food or other administered drugs. Therefore patients are advised to take the Bonviva 150 mg tablet at least 1 hour before breakfast or another oral medicine and to continue standing or sitting upright for at least 1 hour after administration. 

Bisphosphonates such as etidronate are often coprescribed with calcium supplements in the treatment of osteoporosis. If these are ingested concomitantly, the bioavailability of both is significantly reduced with the possibility of therapeutic failure. This may be avoided by allowing a sufficiently long dosage interval a possible approach is to give etidronate for 2 weeks and calcium supplements for 10 weeks in a 12-week period. 

Agents include etidronic acid, pamidronic acid, clodronic acid, alendronic acid, ibandronic acid, rise-dronic acid, zoledronic acid and tiludronic acid. Formulations of clodronic acid and pamidronic acid are available for intravenous administration. The indications for the use of bisphosphonates include treatment of postmenopausal osteoporosis, hypercal-caemia of malignancy and Paget s disease. 

Finally, bisphosphonates have an important place in treatment of osteoporosis of all causes, including steroid-induced osteoporosis. Disodium etidronate, alendronate and clodronate all have potent effects to restore bone mass, and this effect persists for several years of therapy. Newer drugs such as zoledronic acid can be administered by infrequent (once-yearly) infusion, which can help compliance and reduce side effects. 

The bisphosphonates are synthetic organic compounds that are incorporated directly into the hydroxyapatite of bone and then inhibit osteoclastic bone resorption. This antiresorptive action makes them useful in the pharmacological treatment of hypercalcemia, osteoporosis, and Paget s disease. 

Once bone loss is sufficient to result in a compression fracture, pharmacological therapy is much less effective. However, even after fractures have occurred, the use of the bisphosphonates and rPTH has been shown to increase bone densities and reduce the rate of subsequent fractures. Nasal calcitonin (200 units daily) is effective in promoting fracture healing and also exhibits an analgesic effect by reducing pain in persons with acute lumbar compression fractures. Whatever compound is used for prophylaxis or treatment of osteoporosis, calcium and Ds supplementation are required for maximum benefit. 

Studies needed to assess place in therapy with other bisphosphonates Inhibition of bone loss in osteoporosis maypersist up to 2 yr afterb mo of treatment and discontinuation of drug... 

Androgens and anabolic agents have been used in the treatment of osteoporosis, either alone or in conjunction with estrogens. With the exception of substitution therapy in hypogonadism, bisphosphonates have largely replaced androgen use for this purpose. 

Etidronate and the other bisphosphonates exert a variety of effects on bone mineral homeostasis. In particular, bisphosphonates are useful for the treatment of hypercalcemia associated with malignancy, for Paget s disease, and for osteoporosis (see Newer Therapies for Osteoporosis). Contrary to expectations, some of the newer bisphosphonates appear to increase bone mineral density well beyond the 2-year period predicted for a drug whose effects are limited to blocking bone resorption. The bisphosphonates exert a variety of other cellular effects, including inhibition of l,25(OH)2D... 

Teriparatide, the recombinant form of PTH 1-34, is approved for treatment of osteoporosis. Teriparatide is given in a dosage of 20 meg subcutaneously daily. Like fluoride, teriparatide stimulates new bone formation, but unlike fluoride, this new bone appears structurally normal and is associated with a substantial reduction in the incidence of fractures. Teriparatide is approved for use for only 2 years. Trials examining the sequential use of teriparatide followed by a bisphosphonate after 1 or 2 years are in progress and look promising. Giving teriparatide with a bisphosphonate has not shown greater efficacy than the bisphosphonate alone. 

Calcitonin is approved for use in the treatment of postmenopausal osteoporosis. It has been shown to increase bone mass and reduce fractures, but only in the spine. It does not appear to be as effective as bisphosphonates or teriparatide. 

General Category Bisphosphonates Examples Alendronate (Fosamax) Etidronate (Didronel) Ibandronate (Boniva) Pamidronate (Aredia) Risedronate (Actonel) Treatment Rationale and Principal Indications Appear to block excessive bone resorption and formation is used to normalize bone turnover in conditions such as osteoporosis and Paget disease, and to prevent hypercalcemia resulting from excessive bone resorption in certain forms of cancer... 

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