DRUGS that reduce the risk of women with osteoporosis suffering bone fractures have been successfully trialled by the University of Plymouth. Osteoporosis, which weakens bones, usually occurs after menopause through loss of the female hormone oestrogen, and is normally treated with hormone replacement therapy. Plymouth led comprehensive worldwide trials of Alendronate, a non-hormonal drug first trialled in 1996, and found that it significantly replaced lost bone after 12 months, with no major side effects, cutting the risk of fracture by as much as half.