Data Validates Neuroprotective Effect of Quark’s New RNAi product on dying Retinal Ganglion Cells, a Cause of Blindness in Glaucoma

Fremont, CA September 25, 2008 – Quark Pharmaceuticals, Inc., a development-stage pharmaceutical company discovering and developing novel RNA interference (RNAi)- based therapeutics, today announced QPI-1007 as the Company’s first siRNA drug candidate based on its own intellectual property for a host of novel structures having freedom to operate in the siRNA IP space. QPI-1007, which is currently being evaluated in advanced IND enabling preclinical studies as a neuroprotective agent for eye diseases, is the first drug candidate to utilize a novel siRNA structure developed by Quark free of third party IP. The Company is utilizing its proprietary structures and intellectual property to develop additional RNAi drug candidates in its robust pipeline.
Quark has completed studies with QPI-1007 in different animal models of acute and severe optic nerve injury. In collaboration with Prof. Ann Logan of the Division of Medical Sciences, Department of Medicine, University of Birmingham, UK, Quark examined QPI-1007’s effectiveness in a model of retinal ganglion cell (RGC) death by optic nerve crush (ONC). In a second study of QPI-1007 in collaboration with Prof. Adriana Di Polo of the Department of Pathology and Cell Biology, Université de Montréal, its effectiveness was examined in a model of RGC death induced by axotomy of the optic nerve. QPI-1007 displayed neuroprotective activity towards RGCs. It significantly protected retinal neurons against delayed degeneration and reduced injury induced RGC death in vivo, the hallmarks of glaucoma and acute injuries such as ischemic optic neuropathy.
Dr. Daniel Zurr, Quark’s Chief Executive Officer, stated, “With more RNAi products in human trials than any other company in the industry, Quark has proven its ability to advance siRNA products from discovery to the clinic. The in vivo results of QPI-1007 mark a new era for Quark. We can now rely solely on internally-developed novel compositions and proprietary siRNA structures to develop products that have the potential to provide greater efficacy than current treatments. The breadth of our new structures allows us to selectively pick the most efficacious, stable siRNA structure, which is the most suitable for the specific sequence.”
Dr. Logan stated, “QPI-1007 displayed significant neuroprotective activity compared to untreated controls and two different control siRNA molecules in our in vivo model. These results are very exiting. They show that QPI-1007 is a promising drug for ocular neuroprotection.”
Dr. Di Polo commented, “The characteristic visual field changes and loss of vision in glaucoma are caused by the selective degeneration of retinal ganglion cells. Our results suggest that QPI-1007 may be an effective neuroprotective therapy for retinal ganglion cells in acute injuries such as non-artheritic ischemic optic neuropathy, and also in slowprogressing chronic optic nerve injurie s such as glaucoma. QPI-1007 has the potential to serve an unmet medical need for these indications.”

About Quark Pharmaceuticals, Inc.

Quark Pharmaceuticals, Inc. is a development-stage pharmaceutical company engaged in discovering and developing nove l therapeutic RNAi drug candidates. Quark has a fully integrated drug development platform that spans therapeutic target identification to drug development. Quark’s RNAi technology includes novel siRNA structures and chemistry providing Quark with freedom to operate in the siRNA intellectual property arena, as well as the ability to deliver siRNA non invasively to target tissues including the eye, ear, kidney, lung, spinal cord and brain.
PF-4523655 (RTP801i-14), currently in Phase II clinical trials, is a synthetic, chemically modified, siRNA molecule to inhibit the expression of the gene RTP801, licensed to Pfizer. In addition, Quark’s current clinical pipeline includes AKIi-5, developed by Quark for the prevention of acute kidney injury (AKI) following major cardiac surgery, currently in Phase I/IIa clinical trials via systemic delivery and DGFi with open IND for prevention of delayed graft function in kidney transplantation Based on publicly available information, Quark believes AKIi-5 was the first siRNA delivered systemically in a human clinical trial.
In addition, Quark has a broad pipeline of siRNA drug candidates based on novel structures developed internally. The Company expects to utilize the structures to develop additional RNAi drug candidates. Quark is headquartered in Fremont, California and operates research and development facilities in Boulder, Colorado and Ness-Ziona, Israel. Additional information is available at www.quarkpharma.com