Merck Stock Soars to New High on Positive Cancer Vaccine Trial Result

Merck stock surged to a new 52-week high of $154.49 on August 21, after rising 3.4% in morning trading.

The rally follows a landmark cancer vaccine trial result and a cascade of bullish analyst calls.

Morgan Stanley upgraded Merck's stock to Overweight from Equal Weight and more than doubled its price target to $179 from $116, citing the strengthened long-term growth narrative heading into Keytruda's anticipated 2028 patent expiration.