Sanofi Pasteur U.S. operation part of dengue vaccine buildup

Sanofi's ($SNY) highly anticipated dengue vaccine is being manufactured in a facility in France built specifically for the product. But expansion is also going on at Sanofi Pasteur's vaccine operation in Swiftwater, PA, in preparation for a launch of the vax which may happen later this year.

"In the second half of 2014, Sanofi Pasteur began construction of a new formulation, filling and lyophilization facility to manufacture its dengue vaccine candidate, upon licensure," Marisol Péron, Sanofi Pasteur's associate vice president of communications, said in an email. "The new facility for the dengue vaccine candidate will offer additional capacity complementing the fill and packaging facility already in operation in France (Val-de-Reuil)."

Additionally, Péron said the site began construction this year of a new quality-control facility and expansion of an existing building to support both its R&D and its industrial operations teams. Those are expected to be completed in 2017 and 2016 respectively. The company didn't want to provide a cost figure for the projects.

Sanofi Pasteur has invested about €1.5 billion ($1.6 billion) and two decades of work developing the vaccine candidate for dengue fever, a mosquito-borne disease that can be caused by any of four related viruses. The World Health Organization (WHO) has said it is the world's fastest-spreading tropical disease and represents a "pandemic threat." The CDC estimates that 400 million people are infected annually.

Guillaume Leroy, who heads Sanofi Pasteur's dengue program, recently told an audience at the World Vaccine Congress that the company will be seeking approvals in countries in tropical and subtropical climes most affected by the virus, instead of the customary model of going first to the U.S. and Europe.

Sanofi has built a €300 million ($322 million) manufacturing facility in Neuville-sur-Saône, France, to produce the potential blockbuster, which Leroy said would have a capacity to manufacture 100 million doses annually. The plant was started in 2009 and has been producing some of the complex 4-in-1 vaccine since 2013 as Sanofi fine-tunes the operation in anticipation of rolling out the product.

While out front, Sanofi is not alone in developing a vaccine for dengue. Japan's Takeda is also working on a dengue candidate it got by buying Colorado-based Inviragen in 2013 with a $35 million upfront payment and the promise of up to $215 million more in milestone payments.

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