Visterra, Inc., developer of novel medicines to prevent and treat infectious and other major diseases, today announced that it has raised an additional $13M to complete a $26M Series A financing. The Bill & Melinda Gates Foundation and Omega Funds participated with the existing investors - Polaris Venture Partners, Flagship Ventures and Lux Capital.

Proceeds will be used to further develop and validate Visterra's technology platform and advance its proprietary infectious disease product pipeline. The company's lead product candidate, VIS410, is a broad spectrum antibody for the prevention and treatment of both seasonal and pandemic influenza.

"We are very pleased to add the support from the Gates Foundation and Omega Funds to our existing team of high quality investors," said Steven Brugger, CEO of Visterra. "The investment from the Gates Foundation also represents a strong commitment from a world leading foundation which shares our mission to make a significant global impact on the prevention and treatment of infectious diseases. We look forward to a long and productive partnership, including collaborating on additional programs of common interest in the future."

The Bill & Melinda Gates Foundation made this equity investment as part of its program-related investments (PRI) strategy, which aims to support innovation, encourage market-driven efficiencies, and attract external capital to promising global health and development projects. This closing also provides for a potential additional equity investment from Gates as its partnership with Visterra extends to other programs supportive of its global PRI strategy.

"We are excited about this partnership with Visterra," said Trevor Mundel, President of the Global Health Program at the Bill & Melinda Gates Foundation. "Our scientific team has been impressed with Visterra's innovative approach to identify novel targets and design novel drugs in infectious disease. We believe Visterra's technology has broad potential application and are optimistic that our partnership will have a meaningful impact to diseases within the foundation's priority areas."

About Visterra

Visterra discovers and develops novel antibodies for the prevention and treatment of infectious and other major diseases. The company's proprietary antibody discovery platform generates unique structural information that identifies novel target epitopes (sites recognized by antibodies) and guides the design of antibodies which specifically target these epitopes to effectively combat disease. The company's lead antibody product candidate, VIS410, is a broad spectrum monoclonal antibody for the prevention and treatment of both seasonal and pandemic influenza. The company is building a proprietary pipeline of novel antibodies in infectious disease, and continuing to expand its disease area focus through strategic partnerships in infectious and other diseases. The company announced an antibody discovery collaboration deal with Pfizer in September, 2012. Visterra was founded based on the scientific work of Dr. Ram Sasisekharan at MIT, and is currently backed by Polaris Venture Partners, Flagship Ventures, Lux Capital, the Bill & Melinda Gates Foundation, and Omega Funds. For more information please visit www.visterrainc.com.