PDS Biotechnology Corp. and Merck KGaA have entered into an exclusive worldwide licensing agreement under which Merck gains access to PDS’ Versamune nanotechnology platform for two of its preclinical antigen-specific cancer immunotherapies.   PDS will receive an undisclosed upfront payment in cash, as well as development, commercial and sales milestones. PDS will also receive royalties on sales of products incorporating the technology.   Dr. Frank Bedu-Addo, chief executive officer of PDS Biotec...