Merck shares fall 9% despite earnings beat, strong demand for top drugs like Keytruda

Merck reported second-quarter revenue and adjusted earnings that topped estimates as it saw strong sales from its blockbuster cancer drug Keytruda as well as other treatments in its oncology and vaccines portfolios and a new cardiovascular drug. 

The pharmaceutical giant also raised its full-year sales forecast to a range of $63.4 billion to $64.4 billion, however it lowered its adjusted profit guidance to between $7.94 and $8.04 per share.

Shares of Merck fell Tuesday as investors appeared to mull over lighter-than-expected sales of Gardasil.