CTF1-51, a truncated carboxyl-terminal fragment of amyloid precursor protein, suppresses the effects of Aβ42-lowering γ-secretase modulators

► Cleavage of CTF1-51 was not suppressed by γ-secretase modulators. ► Treatment with GSMs did not significantly alter Aβ42 production from CTF1-51. ► CTF1-51 has some properties that reduce the effects of some γ-secretase modulators.