By Michael Erman, Jarrett Renshaw and Patrick Wingrove

Dec 19 (Reuters) - AbbVie, Bristol Myers Squibb, Gilead, Merck and other drugmakers are expected on Friday afternoon to announce agreements with the U.S. government to lower certain prescription drug prices, according to sources familiar with the situation.

Switzerland-based Novartis NOVN.S and Roche ROG.S are also expected to announce deals, Bloomberg News reported on Wednesday. Reuters previously reported that AbbVie was among the companies.

In July, Trump sent letters to leaders of 17 major pharmaceutical companies, outlining how they should provide so-called most-favored-nation prices to the U.S. government's Medicaid health program for low-income people, and guarantee that new drugs will not be launched at prices above those in other high-income countries.

So far five companies have struck deals with the administration to rein in prices. They are Pfizer, Eli Lilly LLY.N, AstraZeneca AZN.L, Novo Nordisk NOVOb.CO and EMD Serono, the U.S. division of Germany's Merck KGaA MRCG.DE.

The remaining 12 are Sanofi SASY.PA, Regeneron REGN.O, Merck MRK.N, Johnson & Johnson JNJ.N, AbbVie ABBV.N, Amgen AMGN.O, Gilead GILD.O, Boehringer Ingelheim, Bristol Myers BMY.N, GSK GSK.L, Novartis, and Genentech, Roche's U.S. unit.

AbbVie, Bristol Myers, Gilead and the White House did not immediately respond to requests for comment. Merck declined to comment.

Novartis has said it is in discussions with the Trump administration and is committed to finding solutions that lower costs for Americans. Roche said it supported Trump's goal of reducing the cost of drugs and encouraged other countries to reward biopharmaceutical innovation.

Trump has long focused on the disparity between drug prices in the U.S. and other wealthy countries, which have government-run health systems that negotiate price discounts.

The specter of tighter price controls by the U.S. government initially spooked investors, but terms of the deals announced so far calmed many of those fears.

Analysts have noted that Medicaid, which accounts for only around 10% of U.S. drug spending, already benefits from substantial price discounts, exceeding 80% in some cases.

Pfizer, which announced its 2026 financial outlook on Tuesday, said the Medicaid discounts would result in price and margin compression next year.

(Reporting by Michael Erman; additional reporting by Deena Beasley; Editing by David Gregorio)

((michael.erman@thomsonreuters.com;))