What happened

Shares of Athenex (ATNX) soared on Wednesday after the pharmaceutical company announced a game-changing merger. By the close of trading, Athenex's stock price was up 22.6% after rising as much as 55% earlier in the day. 

So what

Athenex reached a deal to buy Kuur Therapeutics, the leading developer of off-the-shelf CAR-NKT cell immunotherapies, for as much as $185 million.

"CAR-NKT cells offer a distinct set of advantages over other immune effector cells commonly used for cell therapy," Kuur CEO Kevin Boyle said in a press release. "We are excited that the leadership at Athenex recognizes the significant potential of this approach to provide effective treatment options for patients with both solid and hematological tumors."

Pawn chess pieces are surrounding a king chess piece.

Athenex and Kuur Therapeutics are joining forces to become a leader in cell therapy. Image source: Getty Images.

Kuur's shareholders will receive an up-front payment of $70 million that will be paid mostly in Athenex stock. The deal also includes up to $115 million in milestone payments.

Now what 

Kuur has several products in early-stage trials. It plans to share more data from one of its phase 1 studies at the American Society of Gene & Cell Therapy meeting on May 14.

"We are confident that we can continue to innovate on the NKT cell platform," said Dr. Dan Lang, president of Athenex Cell Therapy. "We aspire to convert cancer into a chronic disease."