Quark Pharmaceuticals receives a Japanese patent for its hypoxia regulated genes

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."