alendronate + etidronate + risedronate

This is a combination of three bisphosphonate drugs—alendronate, etidronate, and risedronate. All three are synthetic analogs of pyrophosphate and act as inhibitors of osteoclast-mediated bone resorption. They are primarily used in the prevention and treatment of osteoporosis and other diseases characterized by excessive bone resorption. Alendronate and risedronate are nitrogen-containing bisphosphonates that inhibit farnesyl pyrophosphate synthase in the mevalonate pathway, disrupting protein prenylation essential for osteoclast function[6][8]. Etidronate is a non-nitrogen-containing bisphosphonate that can be metabolically incorporated into nonhydrolysable ATP analogues, inhibiting ATP-dependent enzymes within osteoclasts[8]. The combination would theoretically provide antiresorptive effects through multiple mechanisms within the same drug class; however, there is no evidence this specific triple combination is marketed or clinically used as a single product.