Calcium acetate capsules are a phosphate binder indicated to reduce serum phosphorus in patients with end stage renal disease (ESRD).

The recommended initial dose of calcium acetate capsules for the adult dialysis patient is 2 capsules with each meal. Increase the dose gradually to lower serum phosphorus levels to the target range, as long as hypercalcemia does not develop. Most patients require 3 to 4 capsules with each meal.

Capsule: 667 mg calcium acetate, USP per capsule.

Patients with hypercalcemia.

Patients with end stage renal disease may develop hypercalcemia when treated with calcium, including calcium acetate. Avoid the use of calcium supplements, including calcium-based nonprescription antacids, concurrently with calcium acetate.

An overdose of calcium acetate may lead to progressive hypercalcemia, which may require emergency measures. Therefore, early in the treatment phase during the dosage adjustment period, monitor serum calcium levels twice weekly. Should hypercalcemia develop, reduce the calcium acetate dosage, or discontinue the treatment, depending on the severity of hypercalcemia.

More severe hypercalcemia (Ca >12 mg/dL) is associated with confusion, delirium, stupor and coma. Severe hypercalcemia can be treated by acute hemodialysis and discontinuing calcium acetate therapy.

Mild hypercalcemia (10.5 to 11.9 mg/dL) may be asymptomatic or manifest as constipation, anorexia, nausea, and vomiting. Mild hypercalcemia is usually controlled by reducing the calcium acetate dose or temporarily discontinuing therapy. Decreasing or discontinuing Vitamin D therapy is recommended as well.

Chronic hypercalcemia may lead to vascular calcification and other soft-tissue calcification. Radiographic evaluation of suspected anatomical regions may be helpful in early detection of soft tissue calcification. The long term effect of calcium acetate on the progression of vascular or soft tissue calcification has not been determined.

Hypercalcemia (>11 mg/dL) was reported in 16% of patients in a 3-month study of solid dose formulation of calcium acetate; all cases resolved upon lowering the dose or discontinuing treatment.

Maintain the serum calcium-phosphorus (Ca x P) product below 55 mg2/dL2.

Hypercalcemia is discussed elsewhere [see Warnings and Precautions (5.1)]

The drug interaction of calcium acetate is characterized by the potential of calcium to bind to drugs with anionic functions (e.g., carboxyl, and hydroxyl groups). Calcium acetate may decrease the bioavailability of tetracyclines or fluoroquinolones via this mechanism.

There are no empirical data on avoiding drug interactions between calcium acetate or calcium acetate capsules and most concomitant drugs. When administering an oral medication with calcium acetate capsules where a reduction in the bioavailability of that medication would have a clinically significant effect on its safety or efficacy, administer the drug one hour before or three hours after calcium acetate capsules or calcium acetate. Monitor blood levels of the concomitant drugs that have a narrow therapeutic range. Patients taking anti-arrhythmic medications for the control of arrhythmias and anti-seizure medications for the control of seizure disorders were excluded from the clinical trials with all forms of calcium acetate.

Administration of calcium acetate in excess of the appropriate daily dosage may result in hypercalcemia [see Warnings and Precautions (5.1)].

Calcium acetate, USP acts as a phosphate binder. Its chemical name is calcium acetate, USP. Its molecular formula is C4H6CaO4, and its molecular weight is 158.17. Its structural formula is:

Each capsule has a light-blue cap imprinted with “AMNEAL” and white body imprinted with “590” with black ink. Each capsule contains 667 mg calcium acetate, USP (anhydrous; Ca(CH3COO)2; MW=158.17 grams) equal to 169 mg (8.45 mEq) calcium. Each capsule also contains the following inactive ingredients: FD&C Blue #1, FD&C Red #3, gelatin, magnesium stearate, polyethylene glycol and titanium dioxide. In addition to the inactive ingredients listed above, each capsule contains Opacode (Black) monogramming ink. Opacode (Black) contains D&C Yellow #10, FD&C Blue #2, FD&C Red #40, iron oxide black and shellac. Opacode (Black) may also contain ethanol, methanol, n-butyl alcohol and propylene glycol.

Calcium acetate capsules, USP are administered orally for the control of hyperphosphatemia in end-stage renal failure.

Meets USP dissolution test 4.

Patients with ESRD retain phosphorus and can develop hyperphosphatemia. High serum phosphorus can precipitate serum calcium resulting in ectopic calcification. Hyperphosphatemia also plays a role in the development of secondary hyperparathyroidism in patients with ESRD.

Effectiveness of calcium acetate in decreasing serum phosphorus has been demonstrated in two studies of the calcium acetate solid oral dosage form.

Ninety-one patients with end-stage renal disease who were undergoing hemodialysis and were hyperphosphatemic (serum phosphorus >5.5 mg/dL) following a 1-week phosphate binder washout period contributed efficacy data to an open-label, non-randomized study.

The patients received calcium acetate 667 mg tablets at each meal for a period of 12 weeks. The initial starting dose was 2 tablets per meal for 3 meals a day, and the dose was adjusted as necessary to control serum phosphorus levels. The average final dose after 12 weeks of treatment was 3.4 tablets per meal. Although there was a decrease in serum phosphorus, in the absence of a control group the true magnitude of effect is uncertain.

The data presented in Table 2 demonstrate the efficacy of calcium acetate in the treatment of hyperphosphatemia in end-stage renal disease patients. The effects on serum calcium levels are also presented.

Table 2: Average Serum Phosphorous and Calcium Levels at Pre-Study, Interim, and Study Completion Time points

a Values expressed as mean ± SE.
b Ninety-one patients completed at least 6 weeks of the study.
c ANOVA of difference in values at pre-study and study completion.

There was a 30% decrease in serum phosphorus levels during the 12 week study period (p<0.01). Two-thirds of the decline occurred in the first month of the study. Serum calcium increased 9% during the study mostly in the first month of the study.

Treatment with the phosphate binder was discontinued for patients from the open-label study, and those patients whose serum phosphorus exceeded 5.5 mg/dL were eligible for entry into a double-blind, placebo-controlled, cross-over study. Patients were randomized to receive calcium acetate or placebo, and each continued to receive the same number of tablets as had been individually established during the previous study. Following 2 weeks of treatment, patients switched to the alternative therapy for an additional 2 weeks.

The phosphate binding effect of calcium acetate is shown in the Table 3.

Table 3: Serum Phosphorous and Calcium Levels at Study Initiation and After Completion of Each Treatment Arm

a Values expressed as mean ± SEM
b ANOVA of calcium acetate vs. placebo after 2 weeks of treatment.

Overall, 2 weeks of treatment with calcium acetate statistically significantly (p<0.01) decreased serum phosphorus by a mean of 19% and increased serum calcium by a statistically significant (p<0.01) but clinically unimportant mean of 7%.

Calcium acetate capsules USP, 667 mg are available as hard gelatin capsules with white opaque body imprinted with “590” and light-blue opaque cap imprinted with “AMNEAL” with black ink. Each capsule contains 667 mg calcium acetate, USP (anhydrous; Ca(CH3COO)2; MW=158.17 grams) equal to 169 mg (8.45 mEq) calcium.

They are supplied as follows:

Bottles of 100:                        NDC 53746-590-01

Bottles of 200:                        NDC 53746-590-20

Bottles of 500:                        NDC 53746-590-05

STORAGE: Store at 20° to 25°C (68° to 77°F); excursions permitted between 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature].

Inform patients to take calcium acetate capsules with meals, adhere to their prescribed diets, and avoid the use of calcium supplements including nonprescription antacids. Inform the patients about the symptoms of hypercalcemia [see Warnings and Precautions (5.1) and Adverse Reactions (6.1)].

Advise patients who are taking an oral medication where reduction in the bioavailability of that medication would have clinically significant effect on its safety or efficacy to take the drug one hour before or three hours after calcium acetate.

Manufactured by:

Amneal Pharmaceuticals Pvt. Ltd.
Oral Solid Dosage Unit
Ahmedabad 382213, INDIA

Distributed By:
Amneal Pharmaceuticals LLC
Bridgewater, NJ 08807

Rev. 07-2020-00