General Information

Miacalcin is a synthetic form of the hormone calcitonin, which inhibits bone loss. 

Miacalcin is indicated for the following:

• for the treatment of symptomatic Paget’s disease of bone in patients with moderate to severe disease characterized by polyostotic involvement with elevated serum alkaline phosphatase and urinary hydroxyproline excretion. 
• for the early treatment of hypercalcemic emergencies, along with other appropriate agents, when a rapid decrease in serum calcium is required, until more specific treatment of the underlying disease can be accomplished. 
• for the treatment of postmenopausal osteoporosis in women greater than 5 years postmenopause. 

Miacalcin is supplied as an injection. Scroll down for the recommended dosing/administration for each indication.

Mechanism of Action

Miacalcin nasal spray, like natural calcitonin, acts primarily by inhibiting osteoclasts, the cells that break down existing bone, thereby decreasing the rate of bone breakdown, allowing the body to build bone naturally.

Side Effects

Adverse effects associated with the use of Miacalcin may include, but are not limited to the following:

•  nausea with or without vomiting
• injection site inflammation
• flushing of the face or hands

Indication 1 : Paget’s disease of bone

Dosing/Administration

The recommended dose of Miacalcin injection for treatment of symptomatic Paget’s disease of bone is 100 USP Units (0.5 mL) per day administered subcutaneously or intramuscularly.

Clinical Trial Results

The trials used for the basis of approval for calcitonin salmon injection for treatment of Paget’s disease of bone were conducted in patients with moderate to severe disease characterized by polyostotic involvement with elevated serum alkaline phosphatase and urinary hydroxyproline excretion. In open-label clinical trials of several months to two years duration with historical controls, biochemical abnormalities were substantially improved (more than 30% reduction) in about 2/3 of patients studied and bone pain was improved in a similar fraction. A small number of documented instances of reversal of neurologic deficits have occurred, including improvement in the basilar compression syndrome, and improvement of spinal cord and spinal nerve lesions. There is too little experience to predict the likelihood of improvement of any given neurologic lesion. Hearing loss is improved infrequently (4 of 29 patients studied by audiometry). Patients with increased cardiac output due to extensive Paget’s disease of bone have had measured decreases in cardiac output while receiving calcitonin salmon. The number of treated patients in this category is too small to predict how likely such a result will be.

There is no evidence that the prophylactic use of calcitonin salmon is beneficial in asymptomatic patients.

Indication 2 - Hypercalcemia

Dosing/Administration

The recommended starting dose of Miacalcin injection for early treatment of hypercalcemia is 4 USP Units/kg body weight every 12 hours by subcutaneous or intramuscular injection. If the response to this dose is not satisfactory after one or two days, the dose may be increased to 8 USP Units/kg every 12 hours. If the response remains unsatisfactory after two more days, the dose may be further increased to a maximum of 8 USP Units/kg every 6 hours.

Clinical Trial Results

In four open-label clinical trials enrolling 53 patients, calcitonin salmon has been shown to lower elevated serum calcium levels of patients with carcinoma (with or without metastases), multiple myeloma, and primary hyperparathyroidism (lesser response). These patients were treated with calcitonin salmon only when other methods of lowering serum calcium (hydration, oral phosphate, corticosteroids) were unsuccessful or unsuitable. With patients’ pre-therapy serum calcium levels as controls, reduction in serum calcium was evident within 1 to 2 hours of administration. The peak effect occurred within 24 to 48 hours of injection and administration of calcitonin salmon every 12 hours maintained a hypocalcemic effect for approximately 5 to 8 days, the time period evaluated for most patients in the clinical trials. The average reduction of 8-hour post-injection serum calcium was approximately 9% (2 to 3 mg/dL). Patients with higher values of serum calcium tended to show greater reductions during calcitonin salmon treatment.

Indication 3 - Post-menopausal osteoporosis 

Dosing/Administration

The recommended dose of Miacalcin injection for treatment of postmenopausal osteoporosis in women greater than 5 years postmenopause is 100 USP Units (0.5 mL) per day administered subcutaneously or intramuscularly. The minimum effective dose of Miacalcin injection for the prevention of vertebral bone mineral density loss has not been established.

Clinical Trial Results

The trials used for the basis of approval for calcitonin salmon injection for treatment of postmenopausal osteoporosis were two randomized, open-label, 2-year studies in postmenopausal women 50 to 74 years of age with total body calcium < 85% of expected normal, and vertebral osteopenia (by x-ray criteria) and/or at least one atraumatic compression fracture. The primary efficacy endpoint was total body calcium measured by neutron activation analysis. Patients were randomized to calcitonin salmon injection 100 International Units daily (subcutaneously or intramuscularly) at bedtime, or control. All subjects received daily supplements of 1200 mg calcium carbonate and 400 International Units of vitamin D.

In both studies, total body calcium increased from baseline with calcitonin salmon therapy at 1 year, followed by a trend to decreasing total body calcium (still above baseline) at 2 years.

Thoracic and lumbar spine X-rays (AP/lateral) were obtained yearly. For the two studies combined (34 calcitonin salmon and 35 control subjects), in the first year there was a total of 6 new vertebral compression fractures in the calcitonin salmon group and 5 in the control group. In the second year there were 7 new fractures in each group.

No evidence currently exists to indicate whether Miacalcin injection decreases the risk of osteoporotic fracture. A controlled study, which was prematurely discontinued, failed to demonstrate any benefit of calcitonin salmon on fracture rate.

No adequate controlled trials have examined the effect of calcitonin salmon injection on vertebral bone mineral density beyond 1 year of treatment. Therefore, the minimum effective dose of Miacalcin injection for prevention of vertebral bone mineral density loss has not been established.

In clinical studies of postmenopausal osteoporosis, bone biopsy and radial bone mass assessments at baseline and after 26 months of daily injectable calcitonin salmon indicate that calcitonin therapy results in the formation of normal bone.