Evofosfamide, a new horizon in the treatment of pancreatic cancer

Evofosfamide, also formerly known as TH-302, is an investigational hypoxia-activated prodrug and is used to target cancerous cells under hypoxic conditions, which is a feature possessed by multiple solid tumors including pancreatic tumors. Gemcitabine, a cytotoxic agent, has for many years been the standard first-line treatment for metastatic pancreatic cancer in patients. In recent years, combination chemotherapeutic therapies have provided a new avenue for molecular targeting by increasing the probability of eliminating the cancer and minimizing the likelihood of resistance. We have evaluated multiple studies in an effort to shed light on an emerging prodrug, evofosfamide, which operates by selectively targeting the tumor hypoxic compartment. A web-based literature search was performed through PubMed and Google Scholar using the keywords 'evofosfamide', 'TH-302,' and 'pancreatic tumor.' Of the available results, 53 relevant studies were reviewed and summarized. Chemotherapeutic agents such as evofosfamide, which targets tumor hypoxia, are new agents against cancer cells. Current experience with these agents is limited as additional and longer prospective studies are needed to further evaluate the clinical efficacy and postmarketing safety profile.

Molecular Pathways: Hypoxia-Activated Prodrugs in Cancer Therapy

Hypoxia is a known feature of aggressive solid tumors as well as a critical hallmark of the niche in aggressive hematologic malignances. Hypoxia is associated with insufficient response to standard therapy, resulting in disease progression and curtailed patients' survival through maintenance of noncycling cancer stem-like cells. A better understanding of the mechanisms and signaling pathways induced by hypoxia is essential to overcoming these effects. Recent findings demonstrate that bone marrow in the setting of hematologic malignancies is highly hypoxic, and that progression of the disease is associated with expansion of hypoxic niches and stabilization of the oncogenic hypoxia-inducible factor-1alpha (HIF1α). Solid tumors have also been shown to harbor hypoxic areas, maintaining survival of cancer cells via the HIF1α pathway. Developing new strategies for targeting hypoxia has become a crucial approach in modern cancer therapy. The number of preclinical and clinical trials targeting low-oxygen tumor compartments or the hypoxic bone marrow niche via hypoxia-activated prodrugs is increasing. This review discusses the development of the hypoxia-activated prodrugs and their applicability in treating both hematologic malignancies and solid tumors. Clin Cancer Res; 23(10); 2382-90. ©2017 AACR.