microRNAs
Future potential with microRNAs
In October 2005, Alnylam and scientists from The Rockefeller University published in the scientific journal Nature on a novel approach to regulate gene expression through the silencing of microRNAs (also known as miRNAs), which are small RNAs that exist naturally within mammalian cells, and are believed to regulate the expression of over one-third of all human genes in the genome. Mutations or aberrant expression of microRNAs has been implicated in cancer, metabolic disease, viral infection, and immune diseases (Krutzfeldt et al. Nature 2005 Dec 1;438(7068):685-9).
microRNAs act as master regulators for physiological pathways or genetic networks to achieve integrated biological functions, and this unique ability to affect the expression of multiple genes in the pathway of disease makes microRNAs an exciting new frontier for drug discovery and development. When inappropriately expressed or mutated, microRNAs represent disease targets whose selective antagonism could result in broad modulation of points on a disease pathway in a manner that is not easily achievable by today's medicines. Indeed, where today's medicines aim to inhibit specific targets in human disease, microRNA therapeutics could interrupt entire disease pathways, thereby affording a greater impact on human disease.
Scientists at Alnylam and The Rockefeller University demonstrated the rational design of a potential new class of chemically modified RNA-based drugs, called 'antagomirs', that specifically silence microRNAs across multiple tissue types following therapeutically relevant administration in animals. The discovery of antagomirs represents the first-ever demonstration of pharmacologic strategy to silence microRNAs and Alnylam believes this research creates the opportunity to design antagomirs that target microRNAs in the context of human diseases, such as cancer and viral infection, amongst many other human diseases.
To better understand and evaluate the opportunity that exists with microRNAs, in 2007, Alnylam and Isis Pharmaceuticals, Inc. formed Regulus Therapeutics Inc. initially as a joint venture which has since transitioned to become an independent company. We believe the combination of expertise, technology and know-how from Isis — a leader in the field of antisense therapeutics, and Alnylam — a leader in the field of RNAi therapeutics, positions Regulus Therapeutics to be a leader in the field of microRNA therapeutics. We are very excited about the opportunity that exists for the development of microRNA therapeutics as it may open up a whole new frontier of pharmaceutical research, where entire pathways of disease, not just single disease targets, define the approach for disease intervention.

