Quark Pharmaceuticals Expands International Patent Protection for Compounds Targeting the RTP801 Gene

Quark Pharmaceuticals Expands International Patent Protection for Compounds
Targeting the RTP801 Gene

FREMONT, Calif. Oct. 26 /PRNewswire/ -- Quark Pharmaceuticals, Inc., a
development-stage pharmaceutical company discovering and developing novel RNA
interference (RNAi)-based therapeutics, today announced issuance of Japanese
Patent Number: 4354633, titled, "Hypoxia regulated genes," on August 7, 2009.
Granted to Quark from a Japanese National Phase application of International
(PCT) Patent Application No. PCT/US98/17296, the patent corresponds to U.S.
Patent No.s 6,455,674, 6,555,667 and 6,740,738 issued by the United States
Patent and Trademark Office.

The granted claims broadly cover various aspects of the RTP801 gene, including
inhibitors targeting either the mRNA or peptide products of the gene. This
patent is part of the intellectual property estate that is the basis of
PF-4523655 (formerly RTP801i-14), a synthetic siRNA molecule licensed to
Pfizer on an exclusive worldwide basis that is designed to inhibit the
expression of RTP801 and is being evaluated in clinical studies for the
treatment of Diabetic Macular Edema (DME), Age-related Macular Degeneration
(AMD). PF-4523655 is currently in Phase II clinical studies for DME and for
wet AMD.

By targeting the RTP801 gene, PF-4523655 has been shown to inhibit abnormal
blood vessel growth and leakage, and to reduce inflammation and suppress
apoptosis in animal models of retinal diseases. Importantly, RTP801 inhibition
differentiates PF-4523655 from other therapeutics designed to specifically
inhibit angiogenesis by targeting either VEGF or its receptors, because it
acts via a VEGF-independent pathway. Hence, PF-4523655 has the potential to
show efficacy when used either as a monotherapy or in combination with
existing VEGF-based therapies.

Daniel Zurr, Ph.D., President and Chief Executive Officer of Quark, said,
"Patents are essential in the drug development process as they protect the
significant investments in R&D and regulatory activities necessary to obtain
marketing approvals and to generate commercial sales. We are vigilant about
upholding our industry leadership position in siRNA R&D by protecting our
pipeline with an aggressive and comprehensive approach to intellectual
property generation and management. . We are also focused on broadening our
intellectual property estate to further protect and enhance the value of our
product pipeline."

About the PF-4523655 (RTP801i-14) Clinical Program
PF-4523655 (RTP801i-14) is a synthetic, siRNA molecule designed to inhibit the
expression of Quark's proprietary target, RTP801. The product candidate is
licensed to Pfizer on an exclusive worldwide basis. Quark discovered RTP801
using its BiFAR(TM) target discovery platform, which identifies clinically
relevant genes and proteins that are critical to reversing a given disease
phenotype when inhibited. The Company owns a family of patents covering the
RTP801 gene and protein sequences, specific antibodies, and gene inhibition
across different disease indications.

The ongoing Phase II study is a prospective, randomized, multi-center,
dose-ranging study is designed to evaluate the safety and efficacy of
PF-4523655 versus laser therapy in 160 patients with DME. In this study,
patients are randomized to receive intravitreal injections of one of three
dose levels of PF-4523655, or laser therapy. Therapeutic effect will be
evaluated by assessing visual acuity and retinal morphology.

About Quark Pharmaceuticals, Inc.
Quark Pharmaceuticals, Inc. is a development-stage pharmaceutical company
engaged in discovering and developing novel RNAi-based therapeutics. 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 for non-invasive
delivery of siRNA to other target tissues including the eye, ear, lung, spinal
cord and brain.

In addition to PF-4523655, Quark's current clinical pipeline includes
QPI-1002, the first systemically administered siRNA drug in human clinical
trials, developed by Quark for the prevention of acute kidney injury (AKI)
following major cardiovascular surgery and the prophylaxis of delayed graft
function after kidney transplantation. Quark has licenses from Silence
Therapeutics and from Alnylam Pharmaceuticals for the structure of these
products.

QPI-1007, a siRNA that utilizes a proprietary structure developed by Quark, is
being evaluated in advanced IND-enabling preclinical studies as a
neuroprotective agent in eye diseases. 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.

Quark Pharmaceuticals, Inc. The Ruth Group (investors / media)
Juliana Friedman Sara Ephraim / Janine McCargo
+972 89 30 5111 (646) 536-7002 / 7033
jfriedman@quarkpharma.com sephraim@theruthgroup.com
jmccargo@theruthgroup.com

SOURCE Quark Pharmaceuticals, Inc.

Juliana Friedman of Quark Pharmaceuticals, Inc., +972-89-30-5111,
jfriedman@quarkpharma.com; or Sara Ephraim, +1-646-536-7002,
sephraim@theruthgroup.com, or Janine McCargo, +1-646-536-7033,
jmccargo@theruthgroup.com