If Pfizer's (NYSE:PFE) mRNA-based coronavirus vaccine candidate ends up coming to market, it will find a ready customer in the U.K. government.

The pharmaceutical giant and its partner, Germany-based BioNTech (NASDAQ:BNTX), announced Monday that they signed a deal with the country to supply 30 million doses of the vaccine. This is pending success in clinical trials and approval from the relevant regulators.

Pfizer and BioNTech did not provide the financial details of the arrangement, but did say that its terms depend on timing and volume of doses.

The news comes on the same day that Pfizer and BioNTech released results from an early phase clinical trial of the candidate, BNT162b1, conducted in Germany. These indicate that the vaccine produced potential coronavirus antibodies that effectively prepared immune systems to attack the coronavirus quickly.

Gloved and masked medical researchers using microscopes in a lab.

Image source: Getty Images.

BNT162b1 utilizes messenger RNA (mRNA), the molecule that transmits detailed instructions from DNA to the body's cells on how to make proteins. The concept is that mRNA can form the basis of a vaccine that triggers the body to produce the necessary antibodies to defeat SARS-CoV-2.

In the press release heralding the U.K. deal, BioNTech CEO Ugur Sahin said that the company is working on similar arrangements with other countries. "We are in advanced discussions with multiple other government bodies and hope to announce additional supply agreements soon," he pronounced. 

BNT162b1 is slated to enter phase 2b/3 clinical trials by the end of this month. Pfizer and BioNTech hope to submit it for regulatory review as soon as October.

On their busy Monday, shares of both companies rose, eclipsing the gains of the key stock exchanges. Pfizer was up by 0.7%, while BioNTech climbed 3.5% higher.