NEW YORK/WASHINGTON — The Trump administration on Thursday scrapped one of its most ambitious proposals for lowering prescription medicine prices, backing down from a policy aimed at health insurers and raising the possibility of new measures focused on drugmakers.

The abandoned proposal would have required health insurers to pass on billions of dollars in rebates they receive from drugmakers to Medicare patients.

The decision represents a new setback to U.S. President Donald Trump’s efforts to deliver on a pledge to lower drug prices for consumers before the November, 2020 elections, when Republicans want to capitalize on voter concern over high healthcare costs.

It allows companies like Cigna Corp and CVS Health Corp, which negotiate rebates with drugmakers on behalf of the government’s Medicare program, to continue to benefit from those discounts.