Novavax is working on a coronavirus candidate vaccine, and shares have soared 70 percent.

Novavax said in an email that the company is working on a candidate vaccine for coronaviruses that are spreading across Asia and are reported to have appeared in the United States. Share price of the vaccine developer rose more than 72 percent in intraday trading on Tuesday to reach $9.99, its biggest intraday gain in more than a decade.

Novavax is working on a coronavirus candidate vaccine, and shares have soared 70 percent.

A third-party spokesman said by email that Novavax plans to recombine nanoparticle vaccine technology for candidate vaccines. Novavax’s Matrix-M adjuvant will be used to enhance the potential immune response.

But not everyone on Wall Street is optimistic about the company, with analysts at B Riley FBR saying “there are more questions than answers”.

Although analyst Mayank Mamtani rated Novavax as a “buy,” the analyst said the rating was based only on the near-term outlook for the flu vaccine developed by the drugmaker, called NanoFlu.

Other drug developers, such as Inovio, BioCryst, Regeneron and Novartis, “also have considerable capacity and a balance sheet advantage” in preventing outbreaks, Mamtani said.