NUC-1031 (SP) is primarily utilized in the field of oncology as a novel prodrug of gemcitabine, designed to enhance the efficacy and reduce the resistance often associated with conventional gemcitabine treatments. It is specifically developed for the treatment of various solid tumors, including pancreatic, ovarian, and biliary tract cancers. The prodrug formulation allows for improved intracellular activation, bypassing key resistance mechanisms and delivering higher concentrations of the active metabolite to cancer cells. This makes it a promising candidate in chemotherapy regimens, particularly for patients who have shown limited response to standard gemcitabine therapy. Clinical trials are ongoing to evaluate its potential in improving patient outcomes and expanding treatment options for difficult-to-treat cancers.