Novavax (NVAX -0.95%) capped its week with the announcement that it has reached a deal with the U.K. government to supply that country with its COVID-19 vaccine candidate. The two sides signed a heads-of-terms agreement to supply the U.K. with 60 million doses of the company's NVX-CoV2373.

The agreement also includes a phase 3 clinical trial to be conducted in the country in order to determine the efficacy of NVX-CoV2373 on the nation's citizenry. This will involve roughly 9,000 adults ages 18 to 85 and is expected to launch in the third quarter of this year. The government will provide infrastructure and other forms of support for the trial.

Child getting a jab from a medical professional.

Image source: Getty Images.

Novavax also said that it will broaden its current agreement through a partnership with FUJIFILM Diosynth Biotechnologies to manufacture the antigen component of the vaccine in that company's U.K. facility.

Although Novavax is considered one of the leading companies in the development of a COVID-19 vaccine, it has only completed the first phase of NVX-CoV2373's clinical trials. Still, the results were very encouraging, as they demonstrated that the candidate produced neutralizing antibodies in every patient dosed for the study.

Novavax is among a clutch of biotechs and pharmaceutical companies working feverishly to develop a vaccine for the disease, which continues to spread around the world. No candidate has yet been approved for use by a major regulator, however.

In its press release heralding the new supply deal, Novavax wrote that "[w]e are honored to partner with the UK government to deliver a vaccine that could provide vital protection in the fight against the global health crisis."

Investors found the company's latest news to be very encouraging. They bid Novavax shares up by nearly 10% on Friday, in sharp contrast to the decline recorded by the S&P 500.