As Sanofi works to gain traction for the launch of its world-first dengue vaccine, a potential competitor may be building its case. This week, the National Institutes of Health announced that a candidate developed by scientists there posted "very encouraging" results, according to the team's lead scientist.

Valneva currently markets Ixiaro, a Japanese encephalitis vaccine and Dukoral, the cholera vaccine it acquired from Johnson & Johnson in 2015. Now, the Lyon, France-based vaccine maker is building on its relationship with the U.S. Department of Defense with a new $42 million supply contract for Ixiaro.

Multiple public health authorities have given insight to the timing of Zika vaccine development, with the WHO now stating that any vaccine may be too late for the current outbreak, a similar situation to the one the world experienced in the Ebola epidemic.

Following Mitsubishi Tanabe's announcement that its tobacco-based flu vaccine could hit the market by 2018 or 2019, a GlobalData analyst has lauded the Japanese company's candidate as poised to "take over" the flu vaccine market from traditional egg-based vaccines.

Citing "seriously flawed" methodology and "unjustified" claims, the journal Vaccine has permanently withdrawn a previously published study critical of Merck's Gardasil.