|Acelerin is a candidate pro-drug. The proposed route to the active monophosphate form is depicted in Scheme 4 in . Acerlarin is an analogue of gemcitabine, the main therapeutic used to treat pancreatic cancer. Acelarin is termed a ProTide, and structurally is gemcitabine with an attached phosphoramidate group. The aim of this chemical modification is to achieve improved cellular delivery of the activated drug, overcoming resistance mechanisms and protecting against enzymatic breakdown to toxic byproducts , and hopefully achieving better disease response. The chemical structure depicted here was drawn from  where acelerin is compound 6f.
Acelarin is the first ProTide to reach clinical trial and is only one member of a large development pipeline covering many nucleoside anti-metabolite anti-neoplastic drugs.