Merck & Co. Inc. (NYSE:MRK) will not exercise its option for Evaxion A/S (NASDAQ:EVAX) Gonorrhea vaccine candidate EVX-B2.Gonorrhoea is a common, sexually transmitted infection caused by Neisseria gonorrhoeae.Consequently, Evaxion retains global rights to EVX-B2 and will look for another potential licensing partner.Gonorrhea infects more than 80 million people worldwide each year. Despite decades of research, no vaccine has been approved to date. Preclinical studies demonstrate that EVX-B2 protects against ...