With an eye toward their bottom lines, big pharmaceutical companies typically invest in research and development for new drugs and vaccines that promise a profit...[the] companies generally assert that they have played an important role in developing and producing essential medicines...Critics fault pharmaceutical companies, however, for investing in "lifestyle" drugs aimed at correcting problems like erectile dysfunction...instead of treatments needed by the poor. Perhaps it is some of this bad press that has led some companies--like GlaxoSmithKline, Astra-Zeneca, and Novartis--to develop centers dedicated to global disease research. For them though, this work is done on a "no-profit, no-loss" model...public and private sector organizations have begun to collaborate more extensively...They include the Medicines for Malaria Venture, which brings together government agencies, research institutions, and private companies...To facilitate research into diseases primarily impacting those in the developing world, advocates have also called for an overhaul of the patent system.