Covid vaccine: UK in talks to access Moderna's highly-effective candidate from spring 2021

Interim data from a late-stage trial indicated Moderna's vaccine was 94.5% effective in preventing COVID-19.

Although Britain has secured a total of 350 million doses of vaccine candidates from six different suppliers - including a Pfizer Inc. vaccine found to be more than 90% effective - it does not have a finalised agreement for the Moderna vaccine.

"As part of the ongoing work of the Vaccines Taskforce, the government is in advanced discussions with Moderna to ensure UK access to their vaccine as part of the wider UK portfolio," a government spokesperson said.

"Moderna are currently scaling up their European supply chain which means these doses would become available in spring 2021 in the UK at the earliest."

Prime Minister Boris Johnson's spokesman said the government had prioritised deals with vaccine developers who could provide early supply to Britain and have advanced manufacturing supply chains in place.

The news from the US biotech firm Moderna comes after similar results were announced last week for a vaccine candidate developed by pharma giant Pfizer and its German partner BioNTech.

Moderna, whose results stem from a clinical trial of more than 30,000 participants, plans to apply for emergency approval of its vaccine and expects to have approximately 20 million doses ready to ship in the US by the end of the year.

"This positive interim analysis from our Phase 3 study has given us the first clinical validation that our vaccine can prevent COVID-19 disease, including severe disease," said Stephane Bancel, Moderna's CEO.

Like the Pfizer candidate, the vaccine involves injecting the body with strands of genetic instructions called "messenger RNA", which tell cells how to fight the coronavirus.

While the breakthrough opens a chink of light at the end of the tunnel, experts caution there are still difficult and dangerous months ahead.

"A vaccine on its own will not end the pandemic," warned World Health Organization head Tedros Adhanom Ghebreyesus.

Supply will initially be limited to health care workers and other vulnerable populations, which could offer major help to hospital systems but will "still leave the virus with a lot of room to move," he said.

Boris Johnson isolating:

As scientists and pharma companies charge ahead on the vaccine front, governments are trying to slow the spread of the virus and protect strained hospital systems.

In hard-hit Europe curbs have returned -- often in the face of protests -- from Greece to Britain, where PM and Covid-19 survivor Johnson was self-isolating out of precaution Monday after coming into contact with an MP who later tested positive for the virus.

Johnson said he would lead the virus response from Downing Street despite the fact "that I've had the disease and I'm bursting with antibodies" after being hospitalised in April.