The stock jumped 12.2 percent on news of the company’s experimental treatment for osteoporosis preventing fractures. Then, in after-market trading, it's risen more than 2 percent on better-than-expected second-quarter earnings. Actually, profit fell 7.6 percent because of restructuring and acquisition charges. Excluding charges, Amgen's profit rose to $1.14 per share (consensus estimate was $1.02). Amgen shares were in the tank last year on negative news concerning its top-selling anemia drugs, Aranesp and Epogen (studies linked them to heart attacks). But what a difference a promising new drug can make. A trial of 7,800 women with osteoporosis found that denosumab strengthened bones and reduced fractures in the spine and hip more than a placebo. Here are stories from AP and Bloomberg.