There are growing concerns that AstraZeneca plc’s Kovid-19 vaccine may impede rare blood clots worldwide vaccination campaigns, from London to Seoul.
A review of possible links to unusual side effects by UK and EU regulators is another blow to Shot, a cheap and easily deployed product that many countries are bidding to end the epidemic.
Safety concerns may shake confidence after increased reports of blood clots in people receiving vaccinations, even though regulators have agreed that the benefits mitigate the risks. Although many regions are drawing their attention to vaccines from Johnson & Johnson and developers in China, Russia and elsewhere, they are in a difficult position, seeking far-flung supply supplements.
“Nothing better than this,” said Michael Kinch, a drug development specialist and Associate Vice Chancellor at Washington University in St. Louis. “In a less-vaccinated country, I think you have no choice but to take it.”
Investigations of the vaccine, developed by AstraZeneca and the University of Oxford, have been particularly acute in Europe, where suspicions about shots were already running high in places such as France and Poland. The UK recommended on Wednesday that people under the age of 30 be offered an alternative to the Astra vaccine, and European Union countries have also imposed age restrictions.
Governments and regulators are looking elsewhere, and in some cases are also taking action. According to Airfinity Ltd, a London-based research firm, AstraZeneca’s shot put accounts for about a quarter of total supply deals for 2021.
Kovacs, an initiative designed to reach a global scale supported by groups including the World Health Organization, is highly dependent on the AstraZeneca vaccine. Shots from Pfizer Ink and Modern Ink are more expensive and harder to store.
Even before the results of the latest reviews in Europe, South Korea went on to temporarily suspend AstraZeneca vaccination for people under 60 years of age.
Meanwhile, Canadian officials are reviewing the new guidance, as well as information submitted by AstraZeneca, and will determine further steps, Federal Health Ministry spokesman Anna Madison wrote in an email. Canada suspended plans in late March citing concerns of blood clots to people under 55 years old.
Regulators believe the vaccine is safe and effective and are leaving it to individual countries to make their own decisions, according to Anthony Haraden, deputy chairman of the UK Joint Committee on Immunization and Immunization. There are not many options for many countries.
“It’s important for the whole world,” he said.
Countries in Africa, such as Namibia, Ivory Coast and Senegal, said they would go ahead with plans to administer the incoming dose, pointing to comments from regulators and the WHO supporting the vaccine. Cameron previously halted Astra inoculation.
“For Namibia it doesn’t change anything,” Namibian Health Minister Kalumbi Shangula said. “It has not been conclusively demonstrated in clinical settings. We still plan to administer the vaccine when we receive it.”
The UK’s move to avoid giving shots to young adults comes after an evaluation by the country’s Medicine and Healthcare Products Regulatory Agency found evidence of a link between the vaccine and the sometimes lethal clots “stronger, but more work is still necessary is.”
AstraZeneca said that it is “studying individual cases to understand the epidemiology and possible mechanisms that may explain these extremely important events.” It is also working with regulators on their request for a new label on their shots, it said in a statement.
UK health officials described clotting syndrome as a rare side effect with heparin, an anticoagulant in which the body makes antibodies against blood platelets. How or why the vaccine may be involved in such a process is still under investigation.
The European Medicine Agency said that abnormal blood clots with low platelets should be listed as having very rare side effects, although the regulator has not issued any guidelines on age.
The EMA’s analysis was based on a review of 86 instances that were reported as of March 22, including 18 fatalities. Some 25 million people had received an Astra shot in the UK and Europe by that point. The agency said that on April 4, 222 of that type of clot were reported out of about 34 million people.
Until now, most cases occurred in women under 60 years of age, within two weeks of vaccination. Health officials said that events usually occur after people have received the first dose, so it is unclear how the second dose may affect people.
Many countries have populations that are significantly lower than in Europe, possibly pointing to a higher risk of clotting, even if it is very rare. For now, it is unclear how the data will be interpreted globally, especially in developing countries that were banking on the widespread use of the shot.
“I agree that epidemiological data suggest that natural infection is far worse than the severity of the side effects of the vaccine,” said Kinch of the University of Washington.
– Assistance from Pius Lukong, Katrina Hoije, Kaula Nhango, Antony Sugajin and Ilya Banaras.