An osteoporosis drug proven to save lives after hip fractures may do so by strengthening the body's immune system, according to geriatrics researchers at Duke University Medical Center. In 2007, Duke researchers reported a 28 percent reduction in death among patients who received zoledronic acid (Reclast) within 90 days of surgery for a hip fracture. Zoledronic acid is a yearly intravenous injection of bisphosphonate that inhibits the progression of bone loss.