The company said it will offer commonly prescribed medications with discounts to its Prime members.
Gov. Gavin Newsom signed a bill Monday that supporters say will greatly reduce the spread of infection.
Ryan Reavis, 36, was arrested in Arizona on drug charges as authorities investigate the late rapper's death.
Earlier drafts of legislation aiming to lower drug prices had elicited stinging criticism.
The same medicine can cost two, three, even six times as much as its lowest price at pharmacies only a few miles apart, data from GoodRx show.
Top Democrats are outdoing themselves in their efforts to take on Big Pharma.
Drugmakers had argued that requiring them to disclose list prices amounted to coercion that would violate their free speech rights under the Constitution.
The group will start with a protest outside the Eli Lilly headquarters in Indianapolis.
The states claim the companies artificially inflated and manipulated prices for more than 100 different generic drugs.
Louisiana and Washington want to pay a flat fee to hepatitis C drug makers, such as Gilead, AbbVie and Merck, for unlimited meds each year.