AstraZeneca is likely to remain "under pressure" this week until Europe's official medicines watchdog delivers an official verdict on the risks associated with the company's COVID-19 vaccine.
Multiple countries around the world have moved to suspend the rollout of AstraZeneca's COVID-19 vaccine in recent days amid concerns it could cause blood clots. Germany, Spain, France, Denmark, Ireland, the Netherlands and Italy have all announced suspensions.
Germany's Paul-Ehrlich-Institut on Monday said it observed "a striking accumulation of a special form of very rare cerebral vein thrombosis (sinus vein thrombosis) in connection with a deficiency of blood platelets (thrombocytopenia) and bleeding in temporal proximity to vaccinations with the COVID-19 vaccine AstraZeneca."
Watch: Germany, France, Italy and Spain halt use of AstraZeneca vaccine
The case has been referred to Europe's top medical watchdog, the European Medicine Agency (EMA). An official verdict is due on Thursday.
The EMA said on Monday that it "currently remains of the view that the benefits of the AstraZeneca vaccine in preventing COVID-19, with its associated risk of hospitalisation and death, outweigh the risks of side effects."
AstraZeneca said there had been 15 events of deep-vein thrombosis and 22 events of pulmonary embolism reported among more than 17 million people vaccinated. Ann Taylor, the firm's chief medical officer, said this was "lower than the hundreds of cases that would be expected among the general population.”
AstraZeneca said there was no evidence of a causal link between its vaccine and blood clotting.
"Blood clots are unfortunately fairly common," said Dr Adam Barker and Dr Tara Raveendran, research analysts at stockbroker Shore Capital.
"Epidemiological studies would put the incidence of blood clots at around 1 in 1,000 people. Importantly, the incidence of blood clots increases significantly with age and can reach 1 in 100 people in those over 80 years of age. In addition, there are also several other important risk factors including (but not limited to) obesity, periods of immobility, male gender, smoking and family history."
Dr Barker and Dr Raveendran said public data they had seen suggested "the risk of blood clots associated with AZD1222 appears to be lower than the level observed in the overall population."
"There is arguably more data to support an increased risk of blood clots from the virus, than there is to support an increased risk of blood clots from the vaccine," the pair wrote in a research note on Monday.
The World Health Organisation (WHO) last week said vaccine rollouts should continue and said there was no cause for alarm. Experts from the WHO will meet on Tuesday to review the data, the BBC reported.
Analysts said the incident could prove damaging for AstraZeneca's reputation even if the blood clot fears prove to be unfounded.
"AstraZeneca's stock price is likely to remain under pressure, and unless the company can control the situation fast, the damage is likely to be big," said Naeem Aslam, chief market analyst at Avatrade.
Michael Hewson, chief market analyst at CMC Markets, said: "This is yet another blow to the credibility of the Oxford vaccine, and ultimately the last thing AstraZeneca, and more importantly the populations of Europe, needs given that of all the vaccines the Oxford jab is by far the easiest to transport."
Jim Reid, a senior strategist at Deutsche Bank, said the reputation of AstraZeneca's vaccine could be permanently tarnished whatever the outcomes of official reviews.
"The problem with this incident is that it’s going to be hard to persuade Europeans that there is no smoke without fire with regards to the AZ vaccine, given the previous travails and misinformation, even if vaccinations resume soon," Reid and his team wrote in a morning note sent to clients.
AstraZeneca makes no profit from its COVID-19 vaccine and so its underlying business performance will be untroubled. However, any damage to its reputation could prove costly.
Shares in the drug maker were up 2.5% on Tuesday to trade at £71.49. AstraZeneca was helped by a rating upgrade to buy from investment bank Jefferies and a bullish note published by Deutsche Bank. The investment bank rates the stock a buy and said its target price for shares was £100.
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