Argentina Follows UK In Backing Oxford/AstraZeneca COVID-19 Vaccine

While the US and EU regulators seem less than keen on the data package offered to date on COVID-19 Vaccine AstraZeneca, Latin American countries are moving quickly to follow the UK in backing the cost-effective and more-easily deliverable option.

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Vaccines Are Seen As Key In The Fight To Control The Pandemic

While debate about the data behind AstraZeneca PLC and Oxford University’s COVID-19 vaccine continues in Europe and the US, countries in South and Central America seem happy to follow the UK's lead and grant temporary authorization to the product which has been hailed as a game-changer globally to tackle the coronavirus pandemic.

The UK’s Medicines and Healthcare products Regulatory Agency granted emergency approval for COVID-19 Vaccine AstraZeneca, formerly known as AZD1222, on 30 December based on interim efficacy and safety data from Phase III trials conducted in the UK and Brazil. The authorization recommends two doses administered with an interval between four to 12 weeks, which will allow the country's National Health Service to prioritize the first dose, providing a level of protection for a greater number of people.

Some observers have expressed concerns about the patchy nature of the submission, with efficacy results ranging from 62% to 70% to 90%, and limited data, especially on the over 65s. However, rather than focusing on efficacy figures, the MHRA, the UK government and Oxford University have been stressing the effectiveness of the vaccine in reducing the severity of COVID-19 illness and keeping people out of hospital.

The practical advantages of COVID-19 Vaccine AstraZeneca over the Pfizer Inc./BioNTech SE and Moderna, Inc. mRNA vaccines – which also have been granted temporary authorizations in either the EU and the US or both – have come to the fore. The former is much cheaper and easier to transport and distribute since it can be stored at normal fridge temperatures like the flu vaccine (2-8°C). 

These factors have seen a number of countries line up behind the UK and first up was Argentina. Hours after the MHRA thumbs-up, the country's drug regulatory agency, ANMAT, granted emergency approval, saying the vaccine offered "an acceptable benefit-risk balance.” Argentina, which signed a contract to buy 22.4 million doses of the AstraZeneca/Oxford vaccine, has already begun vaccinating health workers using 300,000 doses of Russia's Sputnik V vaccine.  (Also see "Coronavirus Notebook: Oxford/AZ Vaccine Nears UK Approval; Argentina OKs Russia's Sputnik V" - Pink Sheet, 24 Dec, 2020.)

Regulators in El Salvador have also given emergency authorization to the vaccine, with the country's president Nayib Bukele tweeting that it represents "a real gamechanger." Mexico is expected to follow suit very shortly, with president Andrés Manuel López Obrador saying he was delighted with the news from the UK and that the MHRA's backing was very reassuring. He noted that Mexico and Argentina teamed up with AstraZeneca and the Carlos Slim Foundation in October to distribute, at no profit during the pandemic, 150 million doses in Latin America, excluding Brazil. Approval in Brazil, which is experiencing the world’s second-deadliest coronavirus outbreak, after the US, is expected mid-January.

SVB Leerink analyst Andrew Berens said in a 31 December investor note that despite the expected availability of two other vaccines, AstraZeneca's offering "has several attributes that could make it easier to distribute, especially early in the vaccine demand curve". He highlighted the advantage of normal refrigerated conditions for at least six months for the product and the fact that the vaccine "will cost just a few dollars per dose."

'Wonderful News,' Says Oxfam

The MHRA support was described by Anna Marriott, health policy manager at aid charity Oxfam, as "wonderful news [which] brings renewed hope at a time of rising infections and unprecedented pressure on health services in the UK and beyond. It is now critical that this hope can be shared by all nations."

Marriott added that Oxford University and AstraZeneca "have made welcome efforts to scale up production and pledged 64% of doses to developing countries, yet their limited production capacity means they are only likely to reach 18% of the world’s population at most in the next year. The longer it takes for vaccines to reach everyone, the greater the risk of new variants of COVID-19 emerging and the possibility that their effectiveness could be undermined."

Marriott called on the company and the university to "openly share their vaccine science and technology with the World Health Organization so that production can take place on a truly global scale. Given that this is a publicly-funded vaccine, the UK government should call on them to do so. No single company can produce enough vaccine for all the world."

EMA Statement

The enthusiasm of the UK regulator and its counterparts in Latin America for COVID-19 Vaccine AstraZeneca is not so evident in the US, where the Food and Drug Administration is waiting for results from a US-based Phase III trial due in the first quarter of 2021, or in the rest of Europe.

The European Medicines Agency, which is working towards conditional marketing authorization of COVID-19 vaccines, issued a statement following the MHRA's decision. It said its rolling review of COVID-19 Vaccine AstraZeneca had assessed "some evidence" from a pooled analysis of interim clinical data from four ongoing trials in the UK, Brazil and South Africa, but that “additional scientific information on issues related to quality, safety and efficacy of the vaccine is deemed necessary to support the rigor required for a CMA and this has been requested from the company.”

The EMA does not specify the precise differences between the temporary authorization that the UK has used to allow COVID-19 Vaccine AstraZeneca to be used and a CMA. However, it says: “EMA… is working towards CMA of COVID-19 vaccines, with all the safeguards, controls and obligations that this imposes. It guarantees that the vaccine meets rigorous EU standards for safety, efficacy and quality and comes with:

• full prescribing information and package leaflet with detailed instructions for safe use;

• a robust risk-management and safety monitoring plan;

• manufacturing controls including batch controls for vaccines and conditions for storage;

• an investigation plan for use in children;

• legally binding post-approval obligations (i.e. conditions) and a clear legal framework for evaluation of emerging efficacy and safety data.”

The Pfizer/BioNTech vaccine, known as Comirnaty, is approved for use in individuals aged 16 years of age and over and the Oxford/AstraZeneca vaccine for use in individuals aged 18 years and over. The EMA has agreed with the sponsors of Comirnaty on a plan to trial the vaccine in children at a later stage. 
(Also see "Pfizer/BioNTech COVID-19 Vaccine Wins EU Approval" - Pink Sheet, 21 Dec, 2020.)