NuCana is a clinical-stage biopharmaceutical company based in Edinburgh, focused entirely on developing cancer treatments using its proprietary ProTide technology. ProTide technology takes established nucleoside analog chemotherapy drugs and chemically modifies them to improve efficacy and tolerability — the modified compounds bypass the cell entry and metabolic activation limitations of conventional nucleoside analogs, delivering a pre-activated drug directly inside cancer cells. NuCana has two active pipeline candidates. NUC-7738 is a ProTide transformation of cordycepin, a naturally occurring compound that was previously undevelopable due to rapid enzymatic breakdown. NUC-7738 works by disrupting RNA polyadenylation, broadly altering gene expression in cancer cells and affecting the tumor microenvironment. It is currently in a Phase 2 trial in combination with Merck's pembrolizumab in PD-1-resistant metastatic melanoma, with final data expected in 2026. NUC-3373 is a ProTide transformation of 5-FU designed to generate higher intracellular drug levels while avoiding 5-FU's toxic byproducts; its Phase 2 colorectal cancer trial was discontinued in 2024 after failing to show superiority over standard therapy, and NuCana is evaluating next steps. NuCana has no approved products and no revenue. The company funds operations through equity raises, and manufacturing is fully outsourced. If a product is approved, NuCana plans to commercialize independently or via licensing partnerships with larger pharmaceutical companies.