The MuriGen Therapeutics strategy of target discovery bypasses the “functional genomics” approaches used prevalently in today’s biotechnology industry. The central premise is that if a gene can be inactivated genetically to cure a disease then pharmacological inhibition of the same corresponding protein will also cure a disease. The result is a mouse with the phenotype of absence of disease and the gene that is implicated in curing that disease.

MuriGen’s strategy is predicated on the fact that the protein being inhibited by a pharmaceutical does
not have to be functioning incorrectly in a patient and does not have to be directly involved in the disease
process. There are many examples of successful drug treatment where the protein being inhibited has no
direct role in disease onset and progression.

A classic example is the inhibition of the renin-angiotensin pathway by either ACE inhibitors or AII receptor blockers in the treatment of hypertension. In only a small fraction of hypertensive patients is this pathway involved in the onset and progression of disease yet these drugs remain among the most widely prescribed and effective drugs available today.

A retrospective review (1) of the top selling pharmaceutical drugs in the market demonstrates that their
discovery can be linked to the particular genes that they target. This is regardless of its direct implication in
the disease being treated. It is MuriGen’s strategy to contribute to the discovery of future target genes that
can be used to find new pharmaceuticals for major unmet medical needs.

(1) Zambrowicz BP, Sands AT. Knockouts Model The 100 Best Selling Drugs - Will They Model The Next 100? Nat Rev Drug Discov. 2003 2:38-51.