By Brendan Pierson

Boehringer Ingelheim sued the U.S. government in an attempt to block a program that gives the Medicare health insurance plan the power to negotiate lower drug prices, joining other drugmakers and business groups claiming that it would stifle development of new medicines.

In a complaint filed on Friday in federal court in New Haven, Connecticut, the privately-held German drugmaker said the program violates the U.S. Constitution by giving federal regulators too much power to dictate drug prices.

The U.S. Department for Health and Human Services (HHS), which oversees the Medicare program for Americans age 65 and older, did not immediately respond to a request for comment.

The drug price negotiation program is part of President Joe Biden's signature Inflation Reduction Act (IRA).

Americans pay more for prescription medicines than people in any other country, and the program aims to save $25 billion annually by 2031 through price negotiations for the drugs most costly to Medicare.

The program already faces several court challenges, including from leading industry groups and drug companies.

Unless it is blocked by a court, HHS will begin negotiations next month over 10 high-priced drugs, to be chosen by the agency. The negotiated prices would take effect in 2026.

Type 2 diabetes treatment Jardiance, which Boehringer shares with U.S. drugmaker Eli Lilly, is considered among the most likely drugs to be chosen for the first round of negotiations.

Other companies that have sued over the program include Johnson & Johnson, Merck & Co and Bristol Myers Squibb.

(Reporting by Brendan Pierson in New York, Editing by Alexia Garamfalvi and Bill Berkrot)