Treatment of Paget's Disease of Bone
The recommended treatment regimen is 40 mg once a day for six months.
Re-treatment of Paget’s Disease Re-treatment with Fosazom sodium tablets may be considered, following a six-month post-treatment evaluation period in patients who have relapsed, based on increases in serum alkaline phosphatase, which should be measured periodically. Re-treatment may also be considered in those who failed to normalize their serum alkaline phosphatase.
What Other Drugs Interact with Fosazom?
If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first.
Severe interactions of Fosazom include:
Fosazom has no known serious interactions with other drugs.
Moderate interactions of Fosazom include:
Fosazom has mild interactions with at least 39 different drugs.
This information does not contain all possible interactions or adverse effects. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns or for more information about this medicine.
Of the patients receiving Fosazom sodium in the Fracture Intervention Trial (FIT), 71% (n=2302) were greater than or equal to 65 years of age and 17% (n=550) were greater than or equal to 75 years of age. Of the patients receiving Fosazom sodium in the United States and Multinational osteoporosis treatment studies in women, osteoporosis studies in men, glucocortico > , 45%, 54%, 37%, and 70%, respectively, were 65 years of age or over. No overall differences in efficacy or safety were observed between these patients and younger patients, but greater sensitivity of some older individuals cannot be ruled out.
Fosazom can cause a severe allergic reaction. Symptoms can include:
- rash or hives
- swelling of your face, lips, or tongue
- trouble breathing
If you have an allergic reaction, call your doctor or local poison control center right away. If your symptoms are severe, call 911 or go to the nearest emergency room.
Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).
Fosazom sodium is not indicated for use in pediatric patients.
The safety and efficacy of Fosazom sodium were examined in a randomized, double-blind, placebo-controlled two-year study of 139 pediatric patients, aged 4 to 18 years, with severe osteogenesis imperfecta (OI). One-hundred-and-nine patients were randomized to 5 mg Fosazom daily (weight less than 40 kg) or 10 mg Fosazom daily (weight greater than or equal to 40 kg) and 30 patients to placebo. The mean baseline lumbar spine BMD Z-score of the patients was -4.5. The mean change in lumbar spine BMD Z-score from baseline to Month 24 was 1.3 in the Fosazom sodium-treated patients and 0.1 in the placebo-treated patients. Treatment with Fosazom sodium did not reduce the risk of fracture. Sixteen percent of the Fosazom sodium patients who sustained a radiologically-confirmed fracture by Month 12 of the study had delayed fracture healing (callus remodeling) or fracture non-union when assessed radiographically at Month 24 compared with 9% of the placebo-treated patients. In Fosazom sodium-treated patients, bone histomorphometry data obtained at Month 24 demonstrated decreased bone turnover and delayed mineralization time; however, there were no mineralization defects. There were no statistically significant differences between the Fosazom sodium and placebo groups in reduction of bone pain. The oral bioavailability in children was similar to that observed in adults.
The overall safety profile of Fosazom sodium in osteogenesis imperfecta patients treated for up to 24 months was generally similar to that of adults with osteoporosis treated with Fosazom sodium. However, there was an increased occurrence of vomiting in osteogenesis imperfecta patients treated with Fosazom sodium compared to placebo. During the 24-month treatment period, vomiting was observed in 32 of 109 (29.4%) patients treated with Fosazom sodium and 3 of 30 (10%) patients treated with placebo.
In a pharmacokinetic study, 6 of 24 pediatric osteogenesis imperfecta patients who received a single oral dose of Fosazom 35 mg or 70 mg developed fever, flu-like symptoms, and/or mild lymphocytopenia within 24 to 48 hours after administration. These events, lasting no more than 2 to 3 days and responding to acetaminophen, are consistent with an acute-phase response that has been reported in patients receiving bisphosphonates, including Fosazom sodium.
Fosazom (Fosamax) is in a drug class of medications called bisphosphonates. Fosamax is prescribed for treating osteoporosis, bone pain from diseases such as breast cancer, multiple myeloma, and Paget's disease. Dosing, side effects, warnings and precautions, and safety during pregnancy should be reviewed prior to taking this medication.
In clinical studies, the incidence of upper gastrointestinal adverse events was increased in patients receiving concomitant therapy with daily doses of Fosazom greater than 10 mg and aspirin-containing products.
Carcinogenesis, Mutagenesis, Impairment of Fertility
Harderian gland (a retro-orbital gland not present in humans) adenomas were increased in high-dose female mice (p=0.003) in a 92-week oral carcinogenicity study at doses of Fosazom of 1, 3, and 10 mg/kg/day (males) or 1, 2, and 5 mg/kg/day (females). These doses are equivalent to approximately 0.1 to 1 times a maximum recommended daily dose of 40 mg (Paget’s disease) based on surface area, mg/m 2 . The relevance of this finding to humans is unknown.
Parafollicular cell (thyro >2 . The relevance of this finding to humans is unknown.
Fosazom was not genotoxic in the in vitro microbial mutagenesis assay with and without metabolic activation, in an in vitro mammalian cell mutagenesis assay, in an in vitro alkaline elution assay in rat hepatocytes, and in an in vivo chromosomal aberration assay in mice. In an in vitro chromosomal aberration assay in Chinese hamster ovary cells, however, Fosazom gave equivocal results.
Fosazom had no effect on fertility (male or female) in rats at oral doses up to 5 mg/kg/day (approximately 1 times a 40 mg human daily dose based on surface area, mg/m 2 ).
What is the dosage for Fosazom (Fosamax)?
The recommended dose for treatment of osteoporosis is 5-10 mg daily or 35-70 mg weekly. Paget's disease is treated with 40 mg once daily for six months.
Since food, other medications, and vitamins can interfere with the absorption of Fosazom, they should be taken at least 30 minutes before Fosazom. In order to avoid chemical irritation of the esophagus (the swallowing tube that connects the mouth with the stomach), Fosazom should be taken with a full glass of plain water immediately upon arising in the morning and never chewed or sucked. It should be avoided by patients with abnormalities of the esophagus which delay esophageal emptying, such as scarring (stricture) or poor motility (achalasia). Patients should also not lie down for 30 minutes after swallowing the tablets. Those patients who are unable to remain upright for at least 30 minutes after taking Fosazom should not take it.
Q: I am a 58 year old female and have taken Fosamax for more than 15 years for osteopenia. I recently had an endoscopy which showed acid reflux and ulcers. The doctor took me off Fosamax and put me on omeprazole 20 mg per day for 90 days. Should I go back on Fosamax now or after 90 days? I also take levothyroxine and protriptyline. Do any of these interact with each other?
A: Fosamax (Fosazom) is classified as a bisphosphonate. Fosamax is approved for the treatment and prevention of osteoporosis in women that are postmenopausal, treatment of osteoporosis in males, the treatment of Paget's disease, and the treatment of glucocorticoid induced osteoporosis in men and women. Fosamax, like any medication, has possible risks, warnings and side effects associated with its use. Under the warnings section of the prescribing information for Fosamax is a discussion regarding the possibility of gastrointestinal mucosa irritation that can occur with use of this medication. Included is the possibility of esophageal ulcers. This is not all of the warnings associated with the medication. Fosamax has the following side effects reported by studied patients taking the medication: acid reflux, gastroesophageal reflux disease and gastric ulcer. These are not all of the possible side effects associated with Fosamax. Specific decisions regarding medication therapy is best made by your physician. Consult with your physician to determine if you should start taking Fosamax again. According to a drug interaction report on your prescription medications: levothyroxine (Synthroid, Levothroid, Levoxyl), protriptyline (Vivactil), omeprazole (Prilosec) and Fosamax, there were no drug interactions detected. For more specific information, consult with your doctor or pharmacist for guidance based on your health status and current medications, particularly before taking any action. Jen Marsico, RPh