Which drug class does alendronate belong to?

Which drug class does alendronate belong to?

• A. SERMs
• B. Calcitonin
• C. Estrogen
• D. Bisphosphonates

Answer: (D)

Alendronate is a bisphosphonate. These drugs bind to bone mineral and are taken up by osteoclasts during bone resorption. Nitrogen-containing bisphosphonates, like alendronate, inhibit an enzyme in the mevalonate pathway (farnesyl pyrophosphate synthase), which disrupts prenylation of proteins crucial for osteoclast function and survival. That impairs osteoclast activity and promotes their death, leading to reduced bone resorption. Over time this increases bone mineral density and lowers fracture risk, making it a common treatment for osteoporosis. This mechanism is distinct from hormonal or receptor-based therapies such as SERMs, calcitonin, or estrogen, which act through different targets rather than inhibiting osteoclasts via mineral binding.

Alendronate is a bisphosphonate. These drugs bind to bone mineral and are taken up by osteoclasts during bone resorption. Nitrogen-containing bisphosphonates, like alendronate, inhibit an enzyme in the mevalonate pathway (farnesyl pyrophosphate synthase), which disrupts prenylation of proteins crucial for osteoclast function and survival. That impairs osteoclast activity and promotes their death, leading to reduced bone resorption. Over time this increases bone mineral density and lowers fracture risk, making it a common treatment for osteoporosis. This mechanism is distinct from hormonal or receptor-based therapies such as SERMs, calcitonin, or estrogen, which act through different targets rather than inhibiting osteoclasts via mineral binding.