MDRNA, Inc, a leading RNAi-based drug discovery and development company, reported in vivo data for bladder and liver cancer demonstrating further advancement of the company's oncology programmes. The company reported a reduction in tumour growth in both liver and bladder cancers by targeting genes key to tumour progression, via both systemic and local delivery with the company's proprietary UsiRNAs delivered by its novel DiLA2 platform. In addition, MDRNA disclosed the establishment of an early collaborative effort with a major international pharmaceutical company, its second such effort.

In a presentation at the 2010 OneMedForum in San Francisco, J Michael French, president & CEO of MDRNA, stated that the company has demonstrated potent anti-tumour activity with a UsiRNA targeting PLK1 (Polo-like Kinase 1), a protein involved in cell mitosis and tumour progression. Data from local (intravesical) application of a PLK1 UsiRNA in a DiLA2 liposome formulation in a mouse orthotopic bladder cancer model demonstrated a PLK1 UsiRNA dose-dependent decrease in bioluminescence in a mouse model of orthotopic bladder cancer, with greater than 90% reduction at a dose of 1 mg/kg. Decreased bioluminescence is generally considered to be a clear indication of reduced tumour growth. This study was conducted in conjunction with the Company's collaborators at the Vancouver Prostate Centre.

The PLK1 UsiRNA has also demonstrated activity in models of orthotopic liver cancer and subcutaneous liver tumours, in which the UsiRNA was delivered by systemic administration of a DiLA2 formulation. MRNA-046, a DiLA2-formulated survivin UsiRNA, has been previously reported to have potent RNAi and anti-tumour activity in bladder and liver cancer. Effective delivery (per RNAi activity and tolerability) of a UsiRNA with DiLA2 liposomes has also been previously reported by MDRNA in non-human primates.

"The data we're reporting regarding the potent activity of a PLK1 UsiRNA further validates the strength and speed at which our proprietary RNAi-based drug discovery platform can generate novel compounds," stated French. "We have demonstrated that UsiRNAs against multiple non-cancer and cancer targets are highly active in rodents and non-human primates, and can be delivered with DiLA2 liposomes by intravenous or local routes. In our oncology programmes, we have now demonstrated significant knockdown of both survivin and PLK1, which are high profile targets implicated in apoptosis and proliferation, respectively. Both of these targets have been difficult to inhibit by traditional small molecule and monoclonal antibody approaches. The ability for a single RNAi drug product to target both an apoptotic and proliferation pathway will provide for a potentially more efficacious therapeutic compound against multiple cancers. Taken as a whole, MDRNA's UsiRNA and delivery technologies represent a unique and proprietary approach to the use of RNAi-based therapeutics to treat human diseases."

The additional early collaborative effort with a major international pharmaceutical company will utilize the broad capabilities of MDRNA's proprietary discovery engine for RNAi therapeutics and its world-class research team. The collaboration will focus on in vivo delivery of siRNAs using MDRNA's DILA2 liposome platform. As part of the collaboration, research teams at MDRNA and the pharmaceutical company will examine safety and efficacy of systemic delivery of siRNA in animal models. Financial details of the collaboration were not disclosed.

"Today we also disclosed the establishment of a second early collaborative effort today," continued French. "Between the collaboration we disclosed in September 2009 and this new effort, we believe we are on track to complete a major R&D collaboration well before our goal of mid 2010."

MDRNA is a biotechnology company focused on the development and commercialization of therapeutic products based on RNA interference (RNAi).