Along with Germany, France and the Netherlands, Italy has signed an agreement with pharmaceutical group AstraZeneca to guarantee the supply of 300 million doses of an experimental vaccine that the company is developing with Oxford University in the UK.

While the vaccine is still being tested, here's what we know about it so far.

How does the vaccine work?

Oxford University's vaccine is one of several in development around the world as scientists race to beat Covid-19.

Officially known as ChAdOx1 nCoV-19 or AZD1222, it works by targeting a spiky structure on the surface of the coronavirus called the S protein, which it uses to attach to human cells and cause an infection.

A model of the SARS-CoV-2 virus. Photo: Jens Schlueter/AFP

The genetic material of the new virus's S protein is placed in a weakened version of a common cold virus from chimpanzees that has been modified to prevent it being able to replicate in humans, so that after injection copies of only the S protein (not the virus) are produced.

The idea is that the body will detect the S protein and develop an immune response, teaching the immune system to attack S proteins in future. If the new virus enters a vaccinated person's body, scientists hope the immune system would target its surface spikes, thereby helping to prevent it binding to cells and reproducing.

The vaccine has been tested on animals and a small number of humans so far, with results that were promising enough for the UK to approve a trial on as many as 10,000 volunteers. That study is currently underway, with results expected to take between two and six months, and trials are due to start in other countries around the world.

“A significant proportion of vaccines that are tested in clinical trials don't work,” warns the Oxford Vaccine Centre, which developed the vaccine with Oxford University’s Jenner Institute.

“If we are unable to show that the vaccine is protective against the virus, we would review progress, examine alternative approaches, such as using different numbers of doses, and would potentially stop the programme.”

Several other potential vaccines are being tested around the world. Photo: Nicolas Asfouri/AFP

When might the vaccine be available in Italy?

If trials show the vaccine works, regulators will still have to approve it before it can be offered to the public.

The European Medicines Agency, which reviews drugs for use within the European Union, says it will fast-track the process to green-light a successful vaccine as soon as possible. In an “optimistic” scenario, that could be at the beginning of 2021, head of vaccines Marco Cavaleri said in May.

Yet Italy's health minister has promised that the first doses will be distributed sooner. The agreement with AstraZeneca includes a batch of 60 million doses that are expected to be delivered by the end of this year, Roberto Speranza told the Corriere della Sera after the deal was signed on June 13th.

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While that timeline has not been confirmed by the developers of the vaccine, Italy hopes to benefit from the fact that Italian companies are involved in manufacturing the shot. 

Advent, a specialised manufacturer based in Pomezia near Rome, has already produced some 13,000 doses of the vaccine for use in clinical trials. And according to Speranza, another company in Anagni – also in Rome's Lazio region – will be responsible for putting the vaccine in vials.

Meanwhile as a founding member of the Inclusive Vaccine Alliance – the four-country partnership that signed the deal with AstraZeneca last weekend – Italy will be guaranteed access to any vaccine the allies choose to invest in.

Italy formed the alliance with France, Germany and the Netherlands earlier this month in order to negotiate jointly with drug developers and push to have a potential vaccine manufactured within Europe, with the goal of making it “accessible, available and affordable” everywhere in the EU.

Who would get vaccinated first?

Once a vaccine becomes available in Italy priority will be given to high-risk groups, according to Walter Ricciardi, a top scientific adviser to Italy's minister of health.

The first people to be offered the shot will include health workers, elderly people and people with conditions that make them particularly vulnerable, followed by the military and the police, Ricciardi told Repubblica.

Vaccination will gradually be extended to the rest of Italy, he said, with health services, GPs and vaccination centres mobilised to “cover the population as quickly as possible”.

How much will it cost?

Getting vaccinated against Covid-19 will be free in Italy, according to health minister Speranza, who confirmed to Corriere della Sera that the government would pay for the vaccine.

“The vaccine is the only definitive solution to Covid-19. As far as I'm concerned it will always be a global public asset, a right for everyone, not the privilege of a few,” he said in a statement.