Merck is to cut 8500 further jobs in an attempt to cut $US2.5 billion from its costs by 2015.
Shares in the US pharmaceutical company rose 2.35% to $US48.73 in New York trading after it announced the cuts.
The BBC reports the new losses, combined with 7500 job cuts announced in 2011 and 2012, amount to 20% of its workforce.
Merck said it will shift its focus to areas it sees as high growth, such as cancer treatment.
It is also pulling products in late-stage trials it estimates will not be so successful and licensing other products to alternative companies.
The company anticipates its costs will be reduced by $US1 billion at the end of 2014, by cutting marketing, administrative, research and development operations.
The BBC reports Merck will also sell property in New Jersey to save costs.