The cost of prescription drugs has gotten out of control and Americans are paying way too much for life-saving treatments.
An amendment to require tribal consultation wasn't even put up for a vote.
Dozens of amendments have been filed so it looks like consideration might take a week or two.
Sen. Jon Tester (D-Montana), the ranking member on the Senate Indian Affairs Committee, joined Republicans in advancing debate on the measure.
Republicans in Congress are still pushing bills to approve the controversial project.