Abexinostat (PCI-24781), 99.21%

Abexinostat, also known as PCI-24781 or CRA-024781, is a novel pan-histone deacetylase (HDAC) inhibitor with potent activity against multiple HDAC isoforms. It primarily targets HDAC1, with a reported Ki of 7 nM, and also shows activity against HDAC2, HDAC3/SMRT, HDAC6, and HDAC10. Abexinostat demonstrates greater than 40-fold selectivity against HDAC8 compared with HDAC1.

As an epigenetic research compound, Abexinostat is widely studied in cancer biology, chromatin regulation, apoptosis, DNA damage response, homologous recombination repair, and cell cycle regulation. It has been investigated in preclinical and clinical research settings, including Phase 1/2 studies.

Key Features

• Novel pan-HDAC inhibitor
• Potently targets HDAC1 with Ki = 7 nM
• Active against HDAC2, HDAC3/SMRT, HDAC6, and HDAC10
• Greater than 40-fold selectivity against HDAC8
• Induces accumulation of acetylated histones and acetylated tubulin
• Promotes p21 expression, PARP cleavage, and γH2AX accumulation
• Studied in tumour cell proliferation, apoptosis, DNA damage, and homologous recombination research
• Suitable for epigenetics, oncology, and cell signalling research
• For research use only

Target Profile

Biological Activity

Abexinostat has demonstrated potent antitumour activity against a range of tumour cell lines, with reported GI50 values ranging from 0.15 µM to 3.09 µM. It has also shown antiproliferative activity in HUVEC endothelial cells, with a reported GI50 of 0.43 µM.

In cellular studies, Abexinostat treatment has been associated with:

In Vitro Research Applications

Cell Line Research Data

HDAC Activity Assay Summary

HDAC activity is commonly assessed using a continuous trypsin-coupled fluorescence assay. In this assay, HDAC enzyme preparations are incubated with Abexinostat at different concentrations, followed by addition of trypsin and fluorogenic acetylated peptide substrates.

In Vivo Research Summary

In mouse xenograft studies, Abexinostat has been evaluated in HCT116 and DLD-1 tumour models. Reported findings include dose-dependent tumour growth inhibition following intravenous administration.

Technical Summary

Storage and Handling Notes

Abexinostat should be handled as a research chemical by trained laboratory personnel using appropriate safety procedures.

Recommended handling considerations include:

• Store according to supplier recommendations
• Prepare stock solutions using suitable solvent, commonly DMSO
• Avoid repeated freeze-thaw cycles of prepared aliquots
• Protect compound solutions from unnecessary exposure to light and moisture
• Use appropriate PPE, including gloves, lab coat, and eye protection
• Dispose of compound waste according to institutional chemical safety procedures

Abexinostat / PCI-24781 / CRA-024781 is a potent pan-HDAC inhibitor with strong activity against HDAC1, HDAC2, HDAC3, HDAC6, and HDAC10. It is widely used in epigenetics and oncology research to study histone acetylation, tubulin acetylation, tumour cell growth inhibition, apoptosis, DNA damage response, RAD51-mediated homologous recombination, and cell cycle arrest. Its broad HDAC inhibition profile makes it a valuable research compound for cancer biology, chromatin regulation, and therapeutic mechanism studies.