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Alendronate (Fosamax)
Alendronate inhibits osteoclast-mediated bone resorption by binding to hydroxyapatite on bone surfaces and blocking the enzyme farnesyl pyrophosphate synthase in the mevalonate pathway.
Alendronate inhibits osteoclast-mediated bone resorption by binding to hydroxyapatite on bone surfaces and blocking the enzyme farnesyl pyrophosphate synthase in the mevalonate pathway. Used for Osteoporosis in postmenopausal women, Osteoporosis in men, Glucocorticoid-induced osteoporosis.
At a glance
| Generic name | Alendronate (Fosamax) |
|---|---|
| Also known as | Fosamax |
| Sponsor | Medical University of South Carolina |
| Drug class | Bisphosphonate |
| Target | Farnesyl pyrophosphate synthase (FPPS); hydroxyapatite binding |
| Modality | Small molecule |
| Therapeutic area | Bone metabolism / Rheumatology |
| Phase | FDA-approved |
Mechanism of action
As a bisphosphonate, alendronate is selectively taken up by osteoclasts during bone resorption. Once internalized, it inhibits farnesyl pyrophosphate synthase, disrupting the prenylation of small GTPases required for osteoclast function and survival. This leads to decreased bone turnover and increased bone mineral density, making it effective for conditions characterized by excessive bone loss.
Approved indications
- Osteoporosis in postmenopausal women
- Osteoporosis in men
- Glucocorticoid-induced osteoporosis
- Paget's disease of bone
Common side effects
- Gastrointestinal upset (nausea, dyspepsia, abdominal pain)
- Esophageal irritation / ulceration
- Musculoskeletal pain
- Headache
- Osteonecrosis of the jaw (rare, long-term use)
Key clinical trials
- A Phase II Trial of RAB001 (LLP2A-Alendronate) for Steroid-Induced Early-Stage Osteonecrosis of the Femoral Head (PHASE2)
- Romosozumab Effects on Bone Density, Muscle Mass, and Spine Surgery Outcomes (PHASE2)
- Prospective, Randomized, Multicenter Clinical Trial of Bisphosphonates Combined With Vancomycin for the Treatment of Cierny-Mader Type I and III Osteomyelitis (PHASE3)
- Alendronate for Osteonecrosis in Adults With Sickle Cell Disease (PHASE2)
- Bone, Exercise, Alendronate, and Caloric Restriction (PHASE4)
- Alendronate to Reduce Pelvic Insufficiency Fractures in Cervical Cancer Patients Undergoing Chemoradiation (PHASE1, PHASE2)
- Bone Turnover Markers and Treatment Efficacy in Postmenopausal Osteoporosis (NA)
- The Optimal Sequential Therapy After Long Term Denosumab Treatment (PHASE4)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Alendronate (Fosamax) CI brief — competitive landscape report
- Alendronate (Fosamax) updates RSS · CI watch RSS
- Medical University of South Carolina portfolio CI