NewLink Genetics Corp. announced Thursday that Merck has begun the submission process that brings the companies a step closer to regulatory approval of NewLink’s Ebola vaccine. The FDA’s approval of the Ebola vaccine would trigger the issuance of a priority review voucher owned by Merck and in which NewLink Genetics has a substantial economic interest. Thereafter, Ames-based NewLink would have the right to monetize its share of interest in the voucher. “Given the recent outbreaks and recurrent risk Ebola poses to global public health, we are encouraged by the potential for this vaccine to address this deadly disease,” said Dr. Charles Link Jr., NewLink’s chairman and CEO.