definiens: means, with respect to a Licensed Compound that is a combination of two or more different Compounds, a Compound that ( i ) is a combination of two or more different Compounds, ( ii ) has one Compound as a constituent component that is in the same Compound Class as one of the Compounds in such Licensed Compound ( such common Compound Class, the ) and ( iii ) is reasonably intended by [COMPANY] for use as a back - up product to replace a Licensed Product that may fail in development . In addition to the foregoing, if the Licensed Compound to which the Back - Up Compound relates is a [COMPANY] Compound for which [COMPANY] has initiated in vivo or clinical development or is a Fast Track Compound, then the Licensed Compound and all Back - Up Compounds to such Licensed Compound must share Compounds in the same Anchor Class . In the event that a Licensed Compound consists of a single Compound, then the Back - Up Compound may be a Compound that is not in the same Compound Class as the Licensed Compound