ion uclide ▁and ▁pe pt ide . ▁For ▁ 1 7 7 Lu ▁and ▁ 9 0 Y ▁this ▁is ▁typically ▁D OT A ▁( t et rac ar box y lic ▁acid , ▁and ▁its ▁variants ) ▁and ▁D TP A ▁( pent etic ▁acid ) ▁for ▁ 1 1 1 In . ▁Other ▁ch el ators ▁known ▁as ▁NOT A ▁( tri az acy cl on on ane ▁tri ac etic ▁acid ) ▁and ▁H Y N IC ▁( h yd raz in onic ot in am ide ) ▁have ▁also ▁been ▁experiment ed ▁with , ▁al beit ▁more ▁for ▁imag ing ▁applications . ▁The ▁som at ost atin ▁analog ue ▁affect s ▁b iod ist ribution ▁of ▁the ▁rad ion uclide , ▁and ▁therefore ▁how ▁effectively ▁any ▁treatment ▁effect ▁can ▁be ▁target ed . ▁Ch anges ▁affect ▁which ▁som at ost atin ▁re ceptor ▁is ▁most ▁strongly ▁target ed . ▁For ▁example , ▁D OT A - lan re ot ide ▁( D OT AL AN ) ▁has ▁a ▁lower ▁aff inity ▁for ▁re ceptor ▁ 2 ▁and ▁a ▁higher ▁aff inity ▁for ▁re ceptor ▁ 5 ▁compared ▁to ▁D OT A - oct re ot ide ▁( D OT AT OC ). ▁ ▁App lications ▁ ▁The ▁body ▁of ▁research ▁on ▁the ▁effect iveness ▁of ▁current ▁PR RT ▁is ▁prom ising , ▁but ▁limited . ▁Complete ▁or ▁partial ▁treatment ▁response ▁has ▁been ▁seen ▁in ▁ 2 0 - 3 0 % ▁of ▁patients ▁in ▁tri als ▁treated ▁with ▁