Here is our updated timeline on the global hunt for coronavirus vaccine:
December 31: New coronavirus identified
China reports a cluster of cases of pneumonia in the city of Wuhan, leading to the identification of a new coronavirus.
January 10: Scientists reveal genome of a new coronavirus
A week and a half after China reports a new form of pneumonia, scientists map the genome sequence of what is later identified as COVID-19, a key first step on the road to finding a vaccine.
January 11: Scientists publish molecular blueprint of the new coronavirus
The coronavirus sequenced genome is published, which marks the start of international efforts to study a vaccine.
March 16: Vaccine trial begins in the US
The US National Institutes of Health begins trial of an "investigational" vaccine on 45 healthy adults, aged 18 to 55, after promising results in animal models.
The trial is funded by the US National Institutes of Health and Massachusetts-based biotechnology company, Moderna Inc, and it is set to last six weeks.
The vaccine is officially named mRNA-1273.
April 2: 'Trials to test tuberculosis vaccine against COVID-19 underway'
France's National Institute of Health and Medical Research says "clinical trials to test the BCG vaccine's efficacy against COVID-19 are underway or about to start in the Netherlands, Germany, France, Spain and Australia."
April 8: At least 115 vaccines being studied in the world
Nature.com says that "the global COVID-19 vaccine R&D landscape includes 115 vaccine candidates, 73 of which currently at exploratory or preclinical stages".
Among the most advanced candidates to have moved into clinical development are vaccines tested by Inovio, Moderna, CanSino Biologicals and the Shenzhen Geno-Immune Medical Institute.
April 13: EU pledges €80 million for vaccine research
The EU funding is earmarked to support German biopharmaceutical company CureVac in developing a vaccine.
April 14: GSK and Sanofi team up to find COVID-19 vaccine
The British-French duo, GlaxoSmithKline and Sanofi announce clinical trials for the second half of 2020, hoping to make - if these trials are successful - the vaccine widely available by the second half of 2021.
April 22: Germany announces the beginning of clinical trials for coronavirus vaccine
Germany's BioNTech and American partner Pfizer are given the green light from the Paul-Ehrlich Institute, the German authority for the certification of vaccines, to begin testing a variety of experimental vaccines on 200 healthy volunteers, aged between 18 and 55.
April 24: University of Oxford begins human trials for coronavirus vaccine
Tests of the ChAdOx1 nCoV-19 drug begin on 1,112 people divided into two groups (half of them receiving a vaccine and the other half a placebo), with the aim to stimulate their immune system to attack the virus.
The drug was created by using a chimpanzee virus which was genetically engineered to carry coronavirus.
The UK government is funding the trial with a €51 million contribution.
Health Secretary Matt Hancock says the drug is reported to have an 80 per cent success rate.
May 13: France-US political row over vaccine priority
The French pharma giant, Sanofi causes a political firestorm by saying it would give the United States priority access to a vaccine as it was the first country to fund the research.
French Secretary of State for Economy and Finance Agnes Pannier-Runacher says it is "unacceptable," while prime minister Edouard Philippe summons Sanofi's CEO for reassurance over the vaccine's distribution.
May 22: University of Oxford/AstraZeneca vaccine enters phase two of its trial
Over 10,000 adults and children take part in phase two of their clinical trial, ten times more than the first phase which began in April.
This phase will study whether different age groups react differently to the vaccine.
A third phase is set to check whether the vaccine protects people from catching coronavirus by studying a large group of over-18s.
June 13: European countries partner up to strike huge vaccine deal
Pharma giant AstraZeneca says it has struck a deal with Germany, Italy, the Netherlands and France for the supply of up to 400 million doses of the vaccine the University of Oxford is trialling.
If it proves successful, delivery will begin by the end of 2020.
The British-Swedish company had already signed similar agreements with Britain, the US, the Norway-headquartered Coalition for Epidemic Preparedness Innovations (CEPI) and the international vaccine alliance Gavi.
An agreement had also been reached with the Serum Institute of India for 1 billion doses.
June 15: London's Imperial College announces beginning of human trials of vaccine
Three hundred healthy people participate in Imperial College's study by receiving two doses of a potential vaccine.
Droplets of liquid carry genetic material into the patient's bloodstream replicating part of the virus inside the body and forcing the immune system to learn how to fight it.
If the test shows a promising response, larger trials will take place later in the year with around 6,000 healthy volunteers.
The study is being financed with around €46 million from the UK government plus another €5.5 million coming from philanthropic donations.
June 16: UK begins using steroid on COVID-19 patients after successful trial
A successful treatment is discovered. It's not a vaccine, but it works.
The University of Oxford finds that low-cost synthetic steroid dexamethasone reduces COVID-19 deaths by up to a third after it tested it on 2,100 people with severe respiratory complications caused by coronavirus.
The UK government says it will start using it on patients immediately and that it has already stockpiled 200,000 courses of the drug.
June 16: Which potential vaccine is leading the race?
By June 16, out of 13 candidates, the vaccine at the most advanced phase of trials is the University of Oxford and AstraZeneca's ChAdOx1 nCoV-19 drug, with studies underway to determine "its efficacy, safety and immunogenicity".
The country working on the highest number of vaccines in a clinical phase by this point is China, followed by US, UK and Germany.
June 25: EU authorises use of anti-viral drug to treat COVID-19
More treatments are identified. The European Medicines Agency (EMA) recommends the anti-viral drug remdesivir be authorised to treat patients with COVID-19 in the European Union.
Touted by Donald Trump and other health officials as a promising treatment, the drug will be tested on adults and adolescents from 12 years of age with pneumonia who require oxygen.
June 27: Ursula von der Leyen hails success of vaccines fundraising campaign
The EU Commission President says more than €6 billion were raised in the campaign launched with activist organisation Global Citizen "Global Goal: Unite For Our Future". It brings the total raised by EU institutions to more than €16 billion.
June 27: Brazil secures up to 100 million doses of vaccine hopeful tested at the University of Oxford
Brazil signs a €113 million agreement with AstraZeneca for access to a vaccine hopeful being tested at the University of Oxford. The deal gives it the right to produce an initial quantity of 30 million doses in December and January when the vaccine is still in the testing phase.
If the vaccine passes clinical trials, Brazil will then be able to produce an additional 70 million doses at an estimated cost of €2.05 each.
The agreement includes the rights to access the vaccine technology and the manufacturing process.
The drug, called ChAdOx1 nCoV-19, is being tested in the UK, Brazil and South Africa.
July 1: 'Positive results' from BioNTech-Pfizer vaccine tests
Pfizer and BioNTech report their experimental BNT162b1 vaccine "is able to produce neutralising antibody responses in humans at or above the levels observed in convalescent sera – and that it does so at relatively low dose levels.".
The vaccine is being tested on 45 participants aged 18 to 55 in the US.
In this phase, the test is aimed at verifying that the vaccine is not toxic and triggers an immune system response against the virus.
There are three other vaccine candidates being tested as part of the BNT162 program.
July 7: Novavax receives $1.6 billion from US government for 100 million vaccines
Novavax receives $1.6 billion (€1.4 billion) from the US government for developing a vaccine including a Phase 3 clinical trial; establishing large-scale manufacturing; and delivering 100 million doses of NVX‑CoV2373, its COVID-19 vaccine candidate, as early as late 2020.
It's part of the US government's Operation Warp Speed, a programme that seeks to begin delivering millions of doses of a safe, effective vaccine for COVID-19 next year.
Regeneron Pharmaceuticals has received $450 million (€397 million) to make and supply its own COVID-19 vaccine candidate, REGN-COV2.
The agreement supports continued manufacturing so that the product could be made available immediately in the US if clinical trials are successful.
July 10: UK rejects chance to join EU's COVID-19 vaccine scheme
The UK officially rejects the opportunity to join the European Union's coronavirus vaccine scheme.
Discussions had been "ongoing" between London and Brussels after the bloc reached out to the UK earlier this month to establish whether it wanted to cooperate on its approach to producing and distributing an effective COVID-19 vaccine.
But the UK government confirms on July 10 that it had decided not to participate in the scheme.
July 12: Vaccine is 'unlikely' by 2021, French scientific council expert says
The probability of having a 100% "effective" vaccine against the coronavirus in 2021 is low, says epidemiologist Arnaud Fontanet, urging the French to "return to more serious habits" in the face of the epidemic risk.
"A vaccine is several years of development, there is of course an unprecedented effort to develop this vaccine but I would be very surprised if we had in 2021 a vaccine which is effective," Fontanet says.
"We will probably have a vaccine that will work partially," he added, insisting that "the end of the epidemic" is still far away.