WASHINGTON — Federal regulators are pressing the Supreme Court to stop big pharmaceutical corporations from paying generic drug competitors to delay releasing their cheaper versions of brand-name drugs. They argue these deals deny American consumers, usually for years, steep price declines that can top 90 percent.

The Obama administration, backed by consumer groups and the American Medical Association, says these so-called “pay for delay” deals profit the drug companies but harm consumers by adding $3.5 billion annually to their drug bills. But the pharmaceutical companies counter that they need to preserve longer the billions of dollars in revenue from their patented products in order to recover the billions they spend developing new drugs. And both the large companies and the generic makers say the marketing of generics often is hastened by these deals.