By Colin Kellaher 



  Shares of Surface Oncology Inc. rose nearly 25% on Wednesday after the immuno-oncology company announced a collaboration with Merck & Co. 


  Surface said it will study its SRF617 investigational antibody therapy in combination with Merck's Keytruda cancer drug in patients with solid tumors. 


  The company separately said it sold about 10.9 million common shares at $2.66 apiece, raising gross proceeds of $28.9 million and exhausting the balance on its $30 million at-the-market facility. 


  Surface shares were recently up 24.8% to $3.32. 


  Write to Colin Kellaher at colin.kellaher@wsj.com