Chroma has developed a drug enhancement strategy involving the attachment of specific chemical motifs onto active drugs as a means of enhancing delivery to intracellular targets, termed "Esterase Sensitive Motif" (ESM) technology. The resulting drug-motif moiety is freely transported into the cell but, once inside, is cleaved by intracellular esterases to give an active charged species which cannot leave the cell easily. Over time, significant cellular accumulation of the charged species occurs, leading to increased potency and duration of action. Chroma entered its first therapeutic agent using this technology, CHR-2845, into clinical development in late 2008. Chroma is currently pursuing a number of leading-edge cancer targets using its ESM technology.

Chroma has also characterised a subset of chemical motifs that are selectively cleaved within monocytes and macrophages. This approach has the potential to provide substantial benefit in the treatment of inflammatory disorders through increasing the therapeutic window when compared to the “parent” drug, by reducing systemic exposure outside of the cells of direct interest (i.e. macrophages). Chroma is applying this technology to a number of key inflammation targets.

Chroma has filed a substantial number of patents covering both specific compounds using the ESM approach along with over-arching concept patents.

Click here to see a visual of Chroma's ESM Technology