Comparative Pharmacology
Head-to-head clinical analysis: ACTONEL WITH CALCIUM COPACKAGED versus PAMIDRONATE DISODIUM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ACTONEL WITH CALCIUM COPACKAGED versus PAMIDRONATE DISODIUM.
ACTONEL WITH CALCIUM (COPACKAGED) vs PAMIDRONATE DISODIUM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
ACTONEL WITH CALCIUM (COPACKAGED) contains risedronate sodium, a bisphosphonate that inhibits osteoclast-mediated bone resorption by binding to hydroxyapatite crystals in bone and inhibiting farnesyl pyrophosphate synthase (FPPS), an enzyme in the mevalonate pathway. This leads to reduced bone turnover and increased bone mineral density. The calcium component is for supplementation to prevent hypocalcemia.
Bisphosphonate that inhibits osteoclast-mediated bone resorption by adsorbing to hydroxyapatite crystals and inhibiting their dissolution, and by inhibiting osteoclast activity via farnesyl pyrophosphate synthase inhibition.
Actonel (risedronate) 35 mg orally once weekly, taken with 6-8 oz of plain water at least 30 minutes before breakfast. Calcium supplement (e.g., 1250 mg calcium carbonate) taken with food at a different time of day.
90 mg intravenously over 2-24 hours every 3-4 weeks for hypercalcemia of malignancy; 60-90 mg intravenously over 2-24 hours every 2-4 weeks for osteolytic bone metastases or Paget disease.
None Documented
None Documented
Terminal elimination half-life of risedronate is approximately 20 hours for the 5 mg daily dose and 480 hours for the 35 mg weekly dose due to prolonged retention in bone; clinically, the drug accumulates in bone and is slowly released.
Triphasic: terminal elimination half-life (t1/2γ) is 27-28 hours, representing slow release from bone. Clinical context: prolonged suppression of bone resorption persists weeks after serum levels become undetectable.
Risedronate is eliminated primarily via renal excretion, with approximately 50% of an absorbed dose excreted unchanged in urine. Unabsorbed drug is eliminated in feces. Total clearance is about 100 mL/min.
Primarily renal; 30-62% of unchanged drug excreted in urine within 72 hours, with the remainder bound to bone and slowly released. Biliary/fecal elimination is negligible (<1%).
Category C
Category D/X
Bisphosphonate and Calcium Supplement
Bisphosphonate