MUMBAI, India — While China was becoming the world’s shop floor, India took its place as the world’s pharmacy, and in recent decades has been the largest provider of cheap, lifesaving medicines in poor countries across the globe.

But most of that medicine has been generic copies of brand-name drugs protected by patents in Europe and the United States. Now a big Swiss drug company, Novartis, may be one legal step away from upending the Indian supply chain by forcing the Indian government to recognize a patent for a cancer treatment heralded as a breakthrough for people with a deadly form of leukemia.  Read more