cpm-1285m is a cell-permeable mutated peptide analogue of cpm-1285 ( Bcl-2 inhibitory peptide). cpm-1285m contains a single substitution of alanine for Leu-151, and exhibits a decrease in Bcl-2 binding affinity with a reduction in IC 50 of ∼15-fold. cpm-1285m can be used as a control of cpm-1285.