Quark Pharmaceuticals' siRNA drug candidates featured in two presentations at Glaucoma & Retinopathies 2010

Jun 25 2010

Quark Pharmaceuticals, Inc., a world leader in the discovery and development of RNAi-based therapeutics, today announced that two of its siRNA drug candidates were featured in the following two presentations at the Glaucoma & Retinopathies 2010 conference, which was held June 21-22, 2010 in London, UK:

• "QPI-1007, an ocular neuroprotective siRNA for ameliorating RGC (retinal ganglion cell) loss," presented by Elena Feinstein, Chief Scientific Officer of Quark Pharmaceuticals.

• "Interference RNA for the treatment of AMD and DME," presented by Kay Rittenhouse, Head Translational Medicine Ophthalmology, Specialty Care Business Unit, Pfizer.

QPI-1007 is a potent neuroprotective siRNA and Quark's first siRNA drug candidate having proprietary structure and chemical modifications. The presentation highlighted preclinical data on the pharmacological features of QPI-1007 and its ocular neuroprotective effects in three different animal models – optic nerve crush, optic nerve axotomy and ocular hypertension model of glaucoma. The presentation also discussed clinical prospects for QPI-1007 as a treatment for non-arteritic ischemic optic neuropathy (NAION), the subject of a Phase I/II clinical trial currently underway.

Dr. Feinstein said, "We are pleased to present additional data supporting the neuroprotective effects of QPI-1007 and its potential in NAION. Preclinical data in rat models of glaucoma are also particularly encouraging because both rats and humans undergo retinal ganglion cells damage as a result of glaucoma. We believe that these animal models are most appropriate for supporting clinical studies in humans, and look forward to further evaluating our first siRNA drug with internally developed structure."

The subject of the presentation by Dr. Rittenhouse was the siRNA compound PF-655 developed by Quark that targets Quark's proprietary gene, RTP801. PF-655 is currently in two Phase II clinical trials, in wet age-related macular degeneration (AMD) and diabetic macular edema (DME). Quark licensed this siRNA therapeutic candidate to Pfizer in 2006; and Pfizer is currently conducting both trials in collaboration with Quark. The presentation reviewed a collection of studies on the efficacy of PF-655 in both preclinical models of diabetic retinopathy and wet-AMD. PF-655 inhibited expression of RTP801 in a dose-related manner, starting as early as from day one after its single intravitreal administration, for up to 14 days.  The RNAi effect may have a longer duration in retinal pigmented epithelium/choroid tissues. In addition, PF-655 decreased fluorescein leakage, a wet-AMD endpoint that is translatable in humans.

Dr. Rittenhouse said, "These preclinical results are consistent with the rationale for our ongoing Phase II clinical studies of PF-655 in both DME and wet-AMD."

Glaucoma and Retinopathies 2010 focused on the latest advances in ocular neuroprotection, drug delivery and anti-vascular therapies. With the number of older people and diabetics rising worldwide, the glaucoma and retinal disease markets will double by 2020. These will remain the largest and fastest-growing areas of the ophthalmic pharmaceuticals market, with combined worldwide revenues of $20bn by 2025, according to Visiongain.