PAC-1(Procaspase-activating compound-1) is the first direct caspase-activating compound with EC50 of 0.22 uM; enhances the activity of procaspase-3 in vitro and induces apoptotic death in cancer cells in culture and in mouse xenograft models.

Apoptosis can be induced when procaspase-3 is activated and converted to caspase-3. Procaspase-activating compound 1 (PAC-1) is a procaspase-3 activator and a potential drug treatment in cancer cell lines with elevated levels of procaspase-3.PAC-1 · s effectiveness was found to be directly proportional to the procaspase-3 concentration present in cells. In cancer cells, PAC-1 had an IC50 value of 3 nM for induction of cell death, whereas in cells from adjacent normal tissue IC50 values of 3.2-8.5 µM were observed.