Merck's stock rose after positive clinical trial results for Winrevair, a pulmonary hypertension drug acquired through the Acceleron Pharmaceuticals acquisition. The company is strategically preparing for the Keytruda patent expiration in 2028 by developing new drugs and potential treatment expansions.

Merck's stock has experienced significant volatility, dropping from $130 to $76 and rebounding to around $100. Despite concerns about Keytruda's patent expiration in 2028, the company shows potential through new drug developments, acquisitions, and a promising pharmaceutical pipeline.

Merck acquired Cidara Therapeutics for $9.2 billion to develop a promising long-acting antiviral drug for influenza, addressing concerns about its post-Keytruda future and expanding its product portfolio with potential blockbuster treatments.

Law firm Halper Sadeh LLC is investigating potential securities law violations and breaches of fiduciary duties for three companies involved in recent merger and acquisition transactions.

Law firm Monteverde & Associates is investigating potential merger deals for four companies, examining whether shareholders are receiving fair compensation in recent acquisition transactions.