In vitro activity: Ilomastat (also known as GM6001 or Galardin) is a member of the hydroxamic acid class of reversible metallopeptidase inhibitors, it is a potent, synthetic, and broad spectrum matrix metalloprotease (MMP) inhibitor for MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, MMP-14, and MMP-26 with Ki values of 0.4 nM, 0.5 nM, 27 nM, 3.7 nM, 0.1 nM, 0.2 nM, 3.6 nM, 13.4 nM, 0.36 nM, respectively. Ilomastat inhibits human skin fibroblast collagenase with Ki of 0.4 nM using the synthetic thiol ester substrate Ac-Pro-Leu-Gly-SCH(i-Bu)CO-Leu-Gly-OEt at pH 6.5. Topical application of Ilomastat prevented corneal ulceration after severe alkali injury and that a combination containing Ilomastat, epidermal growth factor, fibronectin, and aprotinin promoted stable regeneration of corneal epithelium after moderate alkali injury. GM6001 inhibits human skin fibroblast collagenase with Ki of 0.4 nM when assayed with a synthetic thio ester substrate at pH 6.5, with 50-fold selectivity over two bacterial enzymes, thermolysin and Pseudomonas aeruginosa elastase. GM 6001 (0.1 nM - 10 nM) inhibits gelatinase A and gelatinase B produced by T-cells, thus inhibits T-cell homing.

Kinase Assay: Collagenase assay uses the synthetic thiol ester substrate Ac-Pro-Leu-Gly-SCH(i-Bu)CO-Leu-Gly-OEt at pH 6.5. The collagenase concentration is 1-2 nM, and the substrate concentrations are from 0.1 to 0.7 nM. Km is found to vary between 1.5 and 4 mM.

Cell Assay: In MDA-MB-435 cells, GM 6001 increases the respiratory rate by 80% and [3H] thymidine incorporation by 50% when treated for 6 h and 12 h respectively, which suggest that GM 6001 increase DNA synthesis. GM 6001 also increases ERK activity and p38 kinase activity.