Pharmacotherapy of Osteoporosis Exam 1 Flashcards
What are the two groups of pharmacological treatment approaches?
- those that stimulate bone formation
- those that inhibit bone resorption
prescriptions that stimulate bone formation
Parathyroid analogs
prescriptions that inhibit bone formation
- Calcitonin-Salmon
- SERMs & hormone therapy
- Bisphosphonates
- Denosumab
Parathyroid analog drugs
- Teriparatide (Forteo®)
- Abaloparatide (Tymlos®)
- Key is low and intermittent dosing
Parathyroid analogs MOA
- Increase in mature osteoblasts
- Inhibits apoptosis of osteoblasts and osteocytes
- Offsets glucocorticoid-induced osteoporosis by inhibition of apoptosis
Parathyroid analogs adverse effects
- Hypercalcemia
- Orthostatic hypotension (dizziness)
- Osteosarcoma
Bisphosphonate drugs
- Alendronate (Fosamax®, Binosto®, +)
- Risedronate (Actonel®, Atelvia®, +)
- Ibandronate (Boniva®, +)
- Zoledronate (Reclast®, +)
Bisphosphonates MOA
- Bind to hydroxyapatite crystals and embed in the skeleton
- Inhibits osteoclasts
Bisphosphonates Adverse Effects
- GI upset
- Esophagitis
- Osteonecrosis (of the jaw)
- Flu-like febrile illness
- Hypocalcemia in patients who are vitamin D deficient
Bisphosphonate Kinetics
- Oral (Alendronate, Risedronate, Ibandronate) and poorly absorbed
- absorption reduced by Ca++, antacids, iron, etc
- renal excretion
- Transient hypocalcemia (muscle pain) esp in pts who are VitD deficient
Hormone therapy MOA
- Osteoclast differentiation is suppressed
- Apoptosis of pre-osteoclasts is increased
- Osteoblast lifespan is increased
Hormone therapy adverse effects
- Clots (venous thromboembolisms), MI, stroke
* Advantages may not outweigh the risks for long term use
Selective Estrogen-Receptor Modulators (SERMs)
Raloxifene (Evista®)
Selective Estrogen-Receptor Modulators (SERMs)
Raloxifene (Evista®)
Selective Estrogen-Receptor Modulators (SERMs) MOA
- ER agonist in bone
- ER antagonist in breast and uterus
Raloxifene
Positive profile for • Breast cancer • Dec. LDL and total cholesterol • No increased endometrial growth (no inc. cancer risk)
Raloxifene adverse effects
- Hot flashes
- Embolisms
- Stroke
SERM with hormone replacement
- Bazedoxifene with conjugated estrogens
- Combination of estrogens with SERM makes it a tissueselective estrogen complex (TSEC)
- Target group: Post-menopausal women with a uterus
SERM with hormone replacement goal
Relief from vasomotor symptoms PLUS maintenance of bone density
SERM with hormone replacement advantage
Decreased endometrial hyperplasia compared to hormone therapy alone
Calcitonin-Salmon MOA
- Inhibits osteoclasts
- Lowers plasma calcium and phosphate levels
- Encourages bone formation
Denosumab (Prolia®) MOA
- Antibody to RANKL
- Stops activation of osteoclasts
- If a patient has hypocalcemia, this largely takes away their ability to increase plasma calcium naturally