Comparative Pharmacology
Head-to-head clinical analysis: ACTONEL WITH CALCIUM COPACKAGED versus FOSAMAX.
Head-to-head clinical analysis: ACTONEL WITH CALCIUM COPACKAGED versus FOSAMAX.
ACTONEL WITH CALCIUM (COPACKAGED) vs FOSAMAX
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 binding to hydroxyapatite in bone matrix and impairing osteoclast activity through inhibition of farnesyl pyrophosphate synthase.
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.
70 mg orally once weekly for osteoporosis; 10 mg orally once daily for Paget's 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.
Terminal elimination half-life is approximately 10.5 years in bone, reflecting slow release from the skeleton. Plasma half-life after intravenous administration is about 1 hour.
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.
Renal excretion of unchanged drug is the primary route (approximately 50% of absorbed dose). Unabsorbed drug is eliminated in feces. No biliary excretion.
Category C
Category C
Bisphosphonate and Calcium Supplement
Bisphosphonate