FRANKFURT (REUTERS) - BioNTech is buying a production site for its coronavirus vaccine hopeful from Swiss drugs giant Novartis to boost output by several million doses next year and hopes to have the shot ready to file for approval in October.

Chief executive Ugur Sahin said its experimental vaccine, which it is developing with Pfizer, could be reviewed by regulators in late October or early November, among the first in the western world.

"A good vaccine should have an immunisation effect of at least 70-75 per cent and that is also the yardstick that we have set ourselves in order to have a vaccine that can stop the pandemic in a significant way," Mr Sahin said.

BioNTech and Pfizer have previously said this would be possible as early as late October.

The transaction with Novartis, the price tag for which was not disclosed, is part of a push to prepare for a global roll-out of the pair's experimental vaccine, based on the so-called messenger RNA (mRNA) technology.

The facility in the German city of Marburg will be converted to be fully on stream in the first half of 2021 with an annual production capacity up to 750 million doses of the inoculation.

The two companies were previously aiming to supply up to 100 million doses worldwide by the end of this year and an additional 1.3 billion doses by the end of 2021.

Chief financial officer Sierk Poetting said the 2021 output volume target should be increased by several hundred million doses and a precise number would depend on the timing of the production launch and ramp-up speed.

The biotech firm said the facility, with its 300 employees that will join BioNTech, will be one of the largest mRNA manufacturing sites in Europe, alongside two of BioNTech's existing vaccine production sites.

Pfizer said it had at least four production sites in the United States and Europe.