Silence is golden

LONDON—British gene-silencing specialist Silence Therapeutics, a European biopharmaceutical company focusing on RNA interference (RNAi), has forged a partnership with Japan-based Dainippon Sumitomo Pharma Co. Ltd. based on demonstrating the functional delivery of Silence's proprietary siRNA molecules to treat specific targets. The financial details of the collaboration, announced Aug. 27, were not disclosed.

Dr. Keiichi Ono, senior executive officer and executive director of Dainippon's drug research division, says, "Following extensive due diligence in the sector, we have chosen to partner with Silence Therapeutics because of the company's proven ability in the delivery of siRNA molecules and the depth of its experience in this area. We look forward to expanding this collaboration further in the future."

A major advantage of the partnership for the Osaka-based pharma is Silence Therapeutics' AtuRNAi, a novel proprietary short interfering RNA (siRNA) molecule which is chemically modified to improve stability, reduce manufacturing costs and increase yield. The collaboration will also make use of Silence's AtuPLEX delivery technology, which improves functional intracellular uptake, says Iain Ross, chairman and CEO of Silence Therapeutics.

"We are delighted to have signed this agreement with Dainippon Sumitomo Pharma, which further underscores the potential of Silence's science and delivery technology," Ross says. "We anticipate that the initial collaboration will lead to a substantive relationship between our companies."

Discovered in 1998, RNA interference (RNAi) is a natural process that cells use to turn down, or silence, the activity of specific genes. Researchers quickly capitalized on the discovery and developed RNAi into a powerful research tool that is now used in thousands of labs worldwide.

Thomas Christely, CEO of Silence Therapeutics, says the agreement with Dainippon does not allow either company to reveal the details of the partnership.

"Silence Therapeutics will be executing certain in vitro and in vivo studies using Silence's AtuRNAi, a novel proprietary short interfering RNA (siRNA) molecule, and its proprietary systemic delivery system, AtuPLEX, in order to demonstrate functional intracellular delivery to certain targets," Christely says. "Dainippon Sumitomo will also do certain studies."

Silence Therapeutics' core AtuRNAi patents have been granted in Europe, the United States and other territories, making Silence Therapeutics one of only two siRNA companies worldwide with a broad proprietary position on composition of matter for siRNA therapeutics, he says.

"Out of nine human clinical siRNA programs worldwide, there are four human clinical programs with Silence Therapeutics' AtuRNAi molecules, i.e., almost 50 percent of all human clinical programs worldwide are using AtuRNAi molecules, which confirms Silence Therapeutics' leadership in the field of siRNA therapeutics," Christely says. "Three of these human clinical programs are developed by Silence Therapeutics' partners Pfizer and Quark. Silence Therapeutics started in June 2009 with its internal lead product Atu027, a proprietary AtuRNAi molecule formulated with AtuPLEX, in a Phase I human clinical trial for the systemic treatment of solid cancers."

What Dainippon brings to the table is its "extensive biological information on certain targets and significant development capabilities," Christely says. "The ultimate goal of the partnership is to successfully demonstrate functional intracellular uptake by using Silence Therapeutics' AtuRNAi and its AtuPLEX delivery technology, and thereby convince Dainippon Sumitomo to sign a broader research and licensing agreement for the development of siRNA therapeutics. Silence expects to sign more collaboration agreements with other Japanese pharma companies."

Silence Therapeutics has granted a license to AstraZeneca to develop novel AtuRNAi therapeutics against five specific targets. This collaboration was the first industry validation of the potential application of Silence Therapeutics' proprietary AtuRNAi molecules, thus solidifying the company's leadership position in RNAi therapeutics.

Dainippon is a top-10 listed pharmaceutical company in Japan with a diverse portfolio of pharmaceutical, animal health and food and specialty products. The company's strong research and development presence in the areas of CNS, diabetes, cardiovascular disease and inflammation/allergy is based on the merger in 2005 between Dainippon Pharmaceutical Co. Ltd., and Sumitomo Pharmaceuticals Co. Ltd.