A. STEWART CAMPBELL
Corden Pharma International, Inc., 1-B Gill Street, Woburn, MA 01801, USA

INTRODUCTION
The pharmaceutical and biotechnology industries are on the cusp of making oligonucleotide drugs a mainstream reality.  From antisense to more recent approaches such as siRNA, miRNA, shRNA and triplex-forming oligonucleotides (TFOs) (1), never before have there been as many candidates in clinical development targeting so many different diseases (Table 1).  What may at first glance appear as a “sudden surge” in the number of candidates in clinical trials, in reality it reflects the culmination of staggering efforts in research over the past 25 years.  Indeed the simple premise that administration of sequence-specific oligonucleotides can treat or even cure disease by altering gene function and regulation was met with an equally complicated and challenging set of technical hurdles that prevented broad-based translation of this concept from bench to bedside. Apart from improvements in our understanding of the biology and pharmacology of gene regulation, recent advances in oligonucleotide chemistry, formulation and drug delivery technologies have combined to overcome many of the practical hurdles, resulting in an ever-increasing number ...