BRUSSELS (Reuters) - The European Commission said on Monday that positive results announced by U.S. biotech firm Moderna for its COVID-19 vaccine candidate were encouraging and said the bloc was working to sign more supply deals with vaccine makers. Moderna said its experimental vaccine was 94.5% effective in preventing COVID-19, based on interim data from a late-stage clinical trial, becoming the second developer to report results that far exceeded expectations, after Pfizer and BioNTech said last week their vaccine candidate was more than 90% effective. “More encouraging news from #COVID19 vaccine trials w/@moderna,” EU health commissioner Stella Kyriakides said on Twitter. The EU has been in talks with Moderna for its experimental COVID-19 vaccine at least since July, an internal EU document seen by Reuters showed. On Aug. 24 the EU Commission, which conducts talks with vaccine makers on behalf of EU states, said exploratory talks with Moderna had been concluded with the aim of signing a contract for the supply of 80 million doses of its vaccine, with the option of buying another 80 million. “Signing contract w/ @pfizer & @BioNTech_Group later this week, more to come soon,” Kyriakides said on Monday. Last week the Commission reached a deal with Pfizer and BioNTech on the supply of their potential COVID-19 vaccine hours after the companies announced their positive results, EU officials said, adding that the timing was a coincidence. The formal signing of that contract is expected later this week.