FOLATE CONJUGATES: A BOON IN THE ANTI-CANCER THERAPEUTICS

Targeted delivery system is a promising strategy for improving cancer treatment and diagnostics. Molecular targeted drug delivery system has the potential to maximize the cancer treatment efficacy and minimize the toxicity to normal cells.  Folate receptor (FR), an established ovarian cancer marker, is frequently found to be overexpressed in other major epithelial tumors. Overexpression of FR- β in myeloid leukemi as & in inflammatory macrophages, including tumor associated macrophages indicates exploitation of FR for targeted drug delivery. Active research taking place in the field of FR based tumor drug targeting has led to development of FR targeted radioimaging agents and chemotherapeutic agents of highly significant value in the field of oncology.  FR is targeted by using conjugates of folic acid or anti FR antibodies. Though, both these techniques have their own advantages & disadvantages. To date, promising folate targeted antibodies, Farletuzumab & the low molecular weight folate conjugates like EC20, EC145 etc. have moved from phase II to phase III trials. This review focuses on all the developments made so far from discovery of the FR as a potential drug target as well as radioimaging agents which provide clear insights to this targeted drug delivery system of the future.