What’s wrong with AstraZeneca’s COVID vaccine?

New Delhi, India - January 16, 2021. A health worker holding a dose of Covishield vaccine in a hospital during a vaccination campaign in Delhi.

New Delhi, India – January 16, 2021. A health worker holding a dose of Covishield vaccine in a hospital during a vaccination campaign in Delhi.

Studies, published in the New England Journal of Medicine, have shown that certain antibodies are the cause of the sometimes life-threatening blood clots reported in AstraZeneca COVID-19 vaccine recipients.

Recently, the European Union’s medicines regulatory body, the European Medicines Agency (EMA) and the World Health Organization (WHO) had said that there is a ‘plausible but unconfirmed’ link ‘between Vaxzevria, the coronavirus vaccine developed by the Swedish and British company AstraZeneca in collaboration with the British University of Oxford and cases of rare blood clots.

With an exponential increase in cases across the world (133 million and over) and India alone accounting for 12.9 million cases, all hopes are on vaccines. AstraZeneca, in particular, has been hailed as the killer of the virus.

The vaccine can be stored and transported at normal refrigerated temperatures of 2 to 8 degrees Celsius. In addition, thanks to its increased manufacturing capacity, it could be efficiently distributed around the world at low cost. Covishield, which is what the vaccine called in India, is one of two vaccines currently in use in the country, the other being the native Covaxin, made by Bharat Biotech.

The problems encountered by the vaccine do not compromise its effectiveness – data provided by the manufacturer shows an effectiveness rate of 63%. However, the problems that have followed AstraZeneca since announcing its interim test data have eroded its reputation.

Problem plans

We are looking at all of the issues that have affected the vaccine:

Dispute of test data: In November 2020, AstraZeneca published an interim analysis of the clinical trials report indicating that its vaccine had an average efficacy of 70%. While this elicited a lot of relief and joy, it was later revealed that the 70% figure was achieved by combining different doses.

AstraZeneca revealed three data sets – an average efficiency of 70 percent, a high of 90 percent and a low of 62 percent. When a small group of people (3,000) received half the intended dose, then a full dose a month later, the results were promising – 90% effective. However, a larger group (9,000) who received two full doses, one month apart, showed reduced efficacy by 62 percent.

While this did not affect the trials and AstraZeneca admitted the half dose was a mistake, the lack of communication turned out to have damaged its reputation.

Efficiency issues for people over 65: In January, the drug maker had to defend its vaccine against reports from various European countries that its low efficacy rate was between 8 and 11% among people over 65. The fact that this is the main risk group made the allegations more serious. .

Following the reports, the German Vaccine Committee recommended that the vaccine be restricted to people aged 18 to 64 because there was not enough data to analyze the effectiveness for people over 65. .

It was only after the European medicines regulator approved the use of the vaccine for all age groups that France, Germany and other countries revised their booth and approved its use for people. over 65 years old.

Supply issues: Earlier this year, the European Union suggested the drugmaker curtail supplies to the UK after AstraZeneca announced a shortfall in planned shipments of COVID-19 vaccines to the EU. The company had started delivery to the EU in February and had committed to supply the EU with 180 million doses.

On its website, AstraZeneca said that half of the EU’s supply in the second quarter and 10 million doses in the first quarter were to come from the company’s international supply chain. However, export restrictions affected deliveries in the first quarter. He said despite the delays, he aims to deliver 100 million doses in the first half of 2021, of which 30 million are expected to be delivered in the first quarter.

In March, the UK warned there would be a delay in rolling out the vaccine to its population under 50 due to supply issues. The UK blamed the delays in delivering the IBS from Pune for the delay in its vaccination program.

Indonesia also said it would experience delays in its immunization schedule as the country would only receive 20 million doses of the vaccine, instead of the 50 million doses initially agreed.

AstraZeneca has sent a legal opinion to the Pune-based Serum Institute of India (SII) regarding delays in the supply of its vaccines. This comes after SII delayed shipping to the UK and was unable to meet its obligations to other countries that were supposed to receive them.

For its part, SII called on the government to provide financial assistance after India imposed export restrictions to boost its production capacity. Adar Poonawala, managing director of SII, said the government pays her less per dose than she would earn from exporting.

Blood clot woes: In addition to his existing woes, there were the few reports of people who had received the vaccine in March, developing blood clots. Although cases are very rare, this was enough to damage the vaccine’s image and prompt a number of countries to suspend its use, pending a safety review.

Prohibitions: Amid concerns over reports of blood clots in some of the vaccine recipients, a number of countries have either banned its use or restricted it to certain age groups. Germany, Denmark, Spain, Norway, the Netherlands, Italy, France, Sweden and Latvia are among the countries that suspended vaccine deployment in March.

Thailand became the first country outside of Europe to delay its deployment at first, but then moved forward after its prime minister received the first dose on March 16. Belgium has set an age limit for the vaccine and has limited its use to people over 55 years old. The UK has also advised against rolling out the vaccine for its group under 30 and said it was being offered an alternative.

In the meantime, South Korea has announced that it will resume administration of AstraZeneca vaccines for people between the ages of 30 and 60.

With the growing reluctance towards vaccines, these problems, and the frequently changed vaccine guidelines in many European countries, have led to great confusion and growing fear among people.

Despite all the hiccups, however, the EMA and the World Health Organization (WHO) said the vaccine’s benefits outweighed the potential risks. As vaccines from other manufacturers, including Moderna and Pfizer, are difficult to store, transport and more expensive, most countries are counting on AstraZeneca to deal with the current health crisis.