FREMONT, Calif., May 4, 2010 – Quark Pharmaceuticals, Inc., the world leader in clinical development of RNAi-based therapeutics, announced today the presentation of a poster at the 2010 American Transplant Congress titled, “A Nomogram for Predicting Risk of Delayed Graft Function Following Machine Perfusion of Renal Transplants.” The poster presents a new model developed by William Irish, Ph.D. of CTI Clinical Trials and Consulting Services in cooperation with Quark and using recent data from the United Network for Organ Sharing/Organ Procurement and Transplantation Network (UNOS/OPTN) database to predict the risk of delayed graft function (DGF). DGF occurs when kidney recipients require dialysis during the first week following transplantation.

As part of the ATC poster session focused on issues relevant to deceased donor kidney transplantation, Dr. Irish will present the new risk model for predicting the likelihood of DGF in recipients of donor kidneys exposed to machine perfusion. This model showed good agreement with the observed proportion of DGF in a validation data set and was valid across different donor subgroups. This model could potentially help predict the likelihood of DGF. DGF is a significant problem for 24% of all recipients of deceased donor kidneys and 33% of patients who receive kidneys from Extended Criteria Donors (ECDs). ECDs are older donors or donors who may have health issues that, in the past, would have precluded their acceptance. These donors are now accepted, as the number of people waiting for a kidney transplant in the USA has grown progressively and is far in excess of the number of available donor kidneys.

Daniel C. Brennan, MD, professor of medicine, medical director of Renal Transplantation Service, Washington University, St Louis said, “This nomogram builds on prior models and is now applicable to kidneys that have been machine perfused, a growing segment of deceased donor kidneys, especially ECD kidneys which are at increased risk for DGF. With this index in hand, physicians caring for potential transplant patients may better anticipate and assess individual risks during the early post transplant period.”

Daniel Zurr, Ph.D., President and Chief Executive Officer of Quark Pharmaceuticals, said, “We are pleased to share this research with the American Transplant Congress, and to further contribute to the study and treatment of Delayed Graft Function. At this conference, Quark also will present results of a Phase I study evaluating QPI-1002 in 40 transplant recipients of kidneys from deceased donors, including ECD. The data safety monitoring board for the study determined there were no dose-limiting toxicities in any dose cohort and that the results support continued evaluation of QPI-1002 for prophylaxis of DGF in deceased donor transplantation. While QPI-1002 has significance for us and the RNAi industry as the first systemically-delivered siRNA to be tested in human trials, it is also important to the renal transplant community as a completely novel investigational approach to addressing DGF.”

About Quark Pharmaceuticals, Inc.

Quark Pharmaceuticals, Inc is a leader in the discovery and development of novel RNAi therapeutics. Quark has a fully integrated drug development platform that spans therapeutic target identification to drug development. The Company’s technology platform includes novel disease targets and siRNA structures and chemistry, providing Quark with freedom to operate in the siRNA intellectual property arena. Quark’s approach to delivery allows targeting of tissues and organs including the eye, kidney, ear, lung, spinal cord and brain.

Quark’s partner, Pfizer Inc, currently is evaluating PF-4523655 (RTP801i-14) in two Phase 2 clinical studies in patients with diabetic macular edema (DME) and age-related macular degeneration (AMD). PF-4523655 is a synthetic, chemically modified siRNA designed to inhibit the expression of the gene RTP801 that was discovered by Quark through the gene discovery platform BiFARTM. Quark’s development pipeline also features QPI-1002, the first systemically administered siRNA drug in human clinical trials. QPI-1002 is being evaluated for the prevention of acute kidney injury (AKI) following major cardiovascular surgery and the prophylaxis of delayed graft function after kidney transplantation. Enrollment was successfully completed recently in Phase I studies in these indications. For the composition of these products, Quark has obtained licenses from Silence Therapeutics and from Alnylam Pharmaceuticals.

In the first quarter of 2010, Quark initiated a Phase 1/2 study of a new synthetic siRNA, QPI-1007, as a neuroprotective agent for eye diseases. QPI-1007 utilizes a proprietary composition with freedom to operate in the siRNA intellectual property arena that was developed in collaboration with BioSpring GmbH. The structure and modifications utilized in QPI-1007 preserve RNAi activity while ameliorating potential off-target and immunostimulatory effects of siRNAs. In addition, Quark has a broad pipeline of siRNA drug candidates that have arisen from Quark’s research activities. The Company is committed to developing novel siRNA structures and expects to utilize these improvements to develop additional RNAi drug candidates based on the Company’s productive R&D engine.

Quark is headquartered in Fremont, California and operates research and development facilities in Boulder, Colorado and Ness-Ziona, Israel. Additional information is available at