Two years ago Merck and AstraZeneca grabbed the attention of the R&D world with their unusual collaboration pact combining two early-stage cancer treatments into a one-two punch. But their partnership is now part of the regular playbook for developers active in the cancer field. Specialists want a "magic shotgun loaded with pellets aimed at multiple targets in multiple pathways," not just a magic bullet, oncologist George Sledge tells Bloomberg Businessweek. And biopharma companies understand that when longtime rivals collaborate, they can advance drugs that do a much better job at extending the lives of patients. Article