5-Fluorouracil derivatives: a patent review (2012-2014)

Introduction: 5-Fluorouracil (5-FU)-based chemotherapy is the most widely prescribed treatment for gastrointestinal solid tumors, but there are several drawbacks such as toxicities, lack of selectivity and effectiveness as well as the development of resistance that need to be overcome.Areas covered:In this review, the authors present the latest innovations in 5-FU derivatives or combinations with: i) other chemotherapeutic drugs; ii) novel targeted compounds; iii) radiotherapy; iv) mAbs; v) siRNA strategies; and vi) traditional Chinese medicine extracts. Moreover, advances to overcome or determine 5-FU adverse effects and effectiveness are described. Finally, the authors introduce the ongoing clinical trials and highlight the main challenges to be addressed in the future.Expert opinion: Although in the past few years there has been a great advancement in the antitumor effectiveness and selectivity of 5-FU-based therapies, it is envisaged that future approaches using omics' technologies that could determine the tumor heterogeneity may help in identifying additional candidate genes, microRNAs or cytokines involved in both the path mechanisms of 5-FU-related toxicity and its therapeutic efficacy. Moreover, the development of novel targeted 5-FU derivatives or 5-FU-based therapies tailored to individual patients opens up new possibilities in the improvement of the quality of life and survival for those suffering from this devastating disease.