NEW YORK (CNNMoney.com) - Merck & Co. is set to announce plans to cut thousands of jobs and scale back its drugmaking operations to better focus on certain types of drugs, a news report said Saturday.

The Wall Street Journal reported that the plan would be the first big move by Richard Clark, who took over as CEO in May and has been hinting that major changes were needed to turn the troubled drugmaker around.

The report comes as one of Merck's most important products, its cholesterol-lowering drug Zocor, faces losing most of its $5 billion in sales next year when its patent expires.

Merck (Research), hurt by the withdrawal of the painkiller Vioxx last year and what analysts call weakness in its drug pipeline, has seen its stock slide nearly 70 percent over the past five years.

The report also comes as Merck gets set to return to Texas next week to defend itself in a third trial over its withdrawn painkiller, Vioxx. Merck lost its first case in a state court in Texas in August but won its second case in its home state of New Jersey. (Full story).

Estimates that Merck will shed up to several thousand jobs was "a good number to work with," the Journal report quoted one person familiar with the situation as saying.

The person declined to say how many plants might be affected, noting that less than a half-dozen wasn't "far off," the report said.

The plan, which could be announced as early as Monday, includes cuts in operations in the U.S. and abroad as well as tighter focus on certain disease-research areas, the report added.

"We are carefully considering a variety of options to help improve our core business fundamentals" and will provide details by year-end, the report quoted a Merck spokeswoman as saying in a statement.

The spokeswoman wouldn't comment beyond the statement, the report said.