UPDATE 2-EU takes up option to buy 150 million more Moderna COVID-19 shots

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BRUSSELS, June 22 (Reuters) - The European Union has decided to take up an option under a supply contract with drugmaker Moderna that allows the bloc to order 150 million additional COVID-19 vaccines produced by the U.S. biotech firm, the EU Commission said on Tuesday.

The announcement comes a week after CureVac, a German biotech firm, said its COVID-19 vaccine was only 47% effective in a late-stage trial, missing the study's main goal and casting doubt on the potential delivery of hundreds of millions of doses to the EU.

The additional Moderna doses will be delivered next year, the EU executive said in a statement. The shots are part of a contract for 300 million doses, approved in February, of which half has already been ordered by the 27-nation bloc.

The EU has also already ordered another 160 million Moderna shots under an initial supply contract signed in November.

The EU Commission said the second contract with Moderna had also been amended to allow the purchase of vaccines adapted to virus variants as well as jabs for paediatric use and boosters.

A spokeswoman for the Commission said the exercise of the option was part of the EU strategy to build a stock of vaccines for the future that could be used against variants, and was not linked to CureVac's announcement.

As part of its plan for so-called next-generation vaccines, the EU signed a contract with Pfizer and BioNTech in May to reserve up to 1.8 billion doses until 2023.

Both Moderna and Pfizer-BioNTech shots are based on the messenger RNA (mRNA) technology. (Reporting by Francesco Guarascio; Editing by Alex Richardson and Louise Heavens)