definiens: means any and all research, pre clinical and clinical drug development activities, including all activities relating to the identifica tion of mRNA Constructs, the testing of mRNA Constr ucts, test method development and stability testing, toxicolog y, formulation, process development, qualification and validation, Manufacture scale - up, development - stage Manufacturing, quality assurance / quality control, holding / keeping ( whether for disposal or otherwise ), clinical studies, statistical analysis and report writing, the preparation and submission of Regulatory Filings, r egulatory affairs with respect to the foregoing and all other activities necessary or reasonably useful or otherw ise requested or required by a Regulatory Authority as a condition or in support of obtaining or maintaining a Regulatory Approval, and, and will have corresponding meanings . For clarity, ( a ) excludes [ * * * ] and ( b ) w ith respect to a Product, Development shall include mod ifying, enhancing and/or improving such Product ( e. g., changing dosage, formulation, etc . ) provided that s uch modification, enhancement and/or improvement do es not change the Collaboration mRNA Construct(s ) in such Product