Merck&Co fell by 3.09% to trade at $75.16 by 12:07 (16:07 GMT) on Wednesday on the NYSE exchange.
The volume of Merck&Co shares traded since the start of the session was 11.28M. Merck&Co has traded in a range of $75.15 to $77.59 on the day.
The stock has traded at $81.3200 at its highest and $75.1400 at its lowest during the past seven days.
