Indianapolis-based pharmaceutical company Eli Lilly announced Monday that it will sell a generic version of Humalog, its branded insulin product. The generic will cost $137 per vial, or half as much as Humalog. Lilly’s move is seen as a partial concession to lawmakers who have grilled pharma companies about the high cost of life-saving prescription drugs. But the company will keep Humalog at its current price. Why this two-tiered drug strategy?

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