French vaccine maker Valneva is expanding trials of a Covid-19 vaccine candidate called VLA2001, and remains in talks with the European Commission over a potential contract, the company has said.

Valneva shares plunged 42 per cent after Britain said on September 13 that it cancelled its contract for about 100 million doses of the vaccine the company is developing, partly over concerns about when it would win approval for use.

But the shares have regained almost 14pc since, to stand up 71pc since the start of the year.

"Valneva continues discussions with the European Commission regarding a potential VLA2001 supply contract," the company said in a statement.

"The company is also actively pursuing opportunities to make VLA2001 available to other customers, subject to positive Cov-Compare data and regulatory approval."

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