BERLIN — German pharmaceutical company BioNTech says it could start shipping the first coronavirus vaccines ordered by the European Union by the end of the year if the data proves the vaccines are safe and effective.

Mainz-based BioNTech, which is developing the vaccine with U.S. company Pfizer, says “deliveries are anticipated to start by the end of 2020, subject to clinical success and regulatory authorization.”

The two companies said this week, based on early and incomplete test results, their COVID-19 vaccine may be 90% effective.

The European Union announced Tuesday that it has finalized an agreement with BioNTech to buy 200 million doses of vaccine, with an option of 100 million more. The vaccine uses mRNA technology to train the immune system to recognize and attack the virus.

BioNTech said the vaccine supply for the EU is being manufactured at its site in Germany and Pfizer’s plant in Belgium. Assuming positive data and availability of the necessary safety and manufacturing data, Pfizer and BioNTech officials say they expect to produce globally up to 50 million vaccine doses in 2020 and up to 1.3 billion doses in 2021.