THE TAOISEACH MICHEÁL Martin has said the Covid-19 vaccine developed by Janssen, a subsidiary of pharmaceutical company Johnson & Johnson, will be a “big help” in the vaccination rollout. 

An application for conditional approval of the vaccine was yesterday sent to the European Medicines Agency (EMA). A decision on its approval could be reached by mid-March.

With Ireland set to receive 2.2 million doses of the jab, what makes it different from the other vaccines available? 

What type of vaccine is this, and why does that matter?

The Taoiseach said the situation with members of the wider public receiving vaccines will move on in April, May and June, helped by the potential approval of the J&J vaccine. 

“In mid-May all the over-70s, the vaccines will be there. And after that, the other generations,” he told TG4′s 7 Lá programme.

The Health Minister Stephen Donnelly said last week that the over-70s cohort will be fully vaccinated by mid-May.  

Micheál Martin said: “Without a doubt, we are hoping that Johnson & Johnson, and the vaccine that company has, will be available in April at least. And that will be a big help.  

“So, we will have more vaccines from March onwards until June, so a lot of people will be able to get vaccines during that period, and especially even more then in July and August.”

He added that “a lot of people” will be vaccinated by the middle of summer and “there’s no doubt that our lives will be different because of that”.

The J&J vaccine uses viral vector technology, which is the same type of technology used in the Oxford/AstraZeneca vaccine already being administered in Ireland and many other countries. 

This vaccine uses a common-cold causing adenovirus, modified so it cannot replicate, as a “vector” to deliver genetic instructions into human cells, telling them to create a protein of the coronavirus.

This trains the immune system to be ready for the live coronavirus.

The company has used this technology before in an Ebola vaccine and in investigational vaccines for HIV, both of which have accrued long-term safety data.

This technology is different from the messenger RNA (mRNA) vaccines – namely the Pfizer/BioNTech and Moderna vaccines currently available. 

In these vaccines, the virus’s genetic code enters cells and tells them to create antigens. 

These antigens are recognised by the immune system and prepare it to fight the coronavirus. No actual virus is needed to create an mRNA vaccine. 

The biggest benefit of the J&J vaccine is that it only requires a single dose to be effective. 

All of the other vaccines currently available require two-dose schedules.

Secondly, similar to the AstraZeneca vaccine, the J&J doses can also be stored in a standard fridge. This means it can be rolled out a lot more easily across the country.

J&J said its vaccine is estimated to remain stable for two years at -20 degrees Celsius, three months of which can be stored at temperatures of 2-8 degrees. 

The Pfizer and Moderna vaccines are stored at very low temperatures, with the Pfizer jab stored at between -70 and -80 degrees Celsius. 

However, these vaccines can also be kept in a regular refrigerator for a number of days. 

What have clinical trials shown?

J&J said the vaccine is 66% effective at preventing moderate to severe disease from Covid-19 28 days after vaccination, based on Phase 3 clinical trial results published last month. 

The company said the vaccine was 85% effective in preventing severe disease “and demonstrated complete protection against Covid-19-related hospitalisation and death as of day 28”.

The level of protection against moderate to severe Covid-19 infection was found to be 72% in the United States section of the trial, 66% in the Latin America and 57% in South Africa, where a mutant strain of the virus has been dominating.

The overall efficacy from these trials combined was 66%.

Has it been approved in other countries? 

The vaccine has not yet been approved in countries around the world, but South Africa began administering it to healthcare workers today as part of a study by the country’s medical research authority.

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Over 80,000 set to receive vaccine in 'exciting week' for roll-out

Another 420,000 doses will be delivered in South Africa over the next four weeks.

The country suspended its vaccine rollout after a study found the Oxford/AstraZeneca jab failed to prevent mild and moderate illness caused by the South Africa virus variant. 

A nurse at a hospital in Cape Town was the first to be immunised, hours after the first batch of 80,000 doses landed in the country late last night.

Johnson & Johnson has asked US regulators to give emergency authorisation to the vaccine in the United States.

What has the EMA said?

Yesterday, the EMA announced that Janssen (the subsidiary of Johnson & Johnson) submitted an application for conditional authorisation for its Covid-19 vaccine.

The agency said in a statement that a decision to approve the jab could be made by the middle of March. 

Approval will depend on data relating to the vaccine’s efficacy, safety and quality being “sufficiently comprehensive”, the EMA said.

The EMA said it has already reviewed some data from Janssen as part of the vaccine’s development, including how well it triggers the production of antibodies and immune cells and clinical safety data.

This “rolling review” has been taking place since 1 December. 

How many doses will the EU/Ireland receive? 

Last October, the EU reached a deal with Johnson & Johnson to obtain 200 million doses of the vaccine for distribution among member states.

The EU said 100 million doses should be delivered by June if it is approved. 

Ireland is set to receive 2.2 million doses in total, according to the government’s vaccine rollout strategy.  

Additional reporting by AFP and Press Association