definiens: means any of ( i ) each of PRO051 and PRO044 and ( ii ) compounds comprising an antisenseoligonucleotide ( ) that is directed to exon skipping by a mechanism intended to directly induce single exonskipping in the dystrophin gene for the treatment of DMD for the relevant exons of the Exon 51 Program, the Exon 44Program, the DMD Program 3, or the DMD Program 4, as applicable, and meeting the criteria set by the JSC for therelevant PROSENSA Collaboration Program, unless otherwise mutually agreed by the JSC, and, in the case of ( i ) or ( ii),all derivatives and improvements of such compound, ( a ) that are existing as of the Effective Date or ( b ) that areResearched and/or Developed by PROSENSA under a PROSENSA Collaboration Program or ( c ) as identified, furthermodified, optimized or otherwise Researched or Developed by [COMPANY] under a [COMPANY] Development Program