Experts propose widening interval between vaccine shots in bid to tackle Portugal’s “avalanche of people arriving in hospitals”

Health authority experts on the technical vaccination commission have recommended widening the interval between administering current two-dose Covid vaccines ‘so that more people can be protected in a short period of time, bearing in mind the current epidemiological situation of the country’, and supply issues – which have seen vaccine deliveries come through much slower than hoped.

Epidemiologist Manuel Carmo Gomes has told Público: “At this very critical time, and to try and contain the avalanche of people arriving at hospitals, we recommend a change in strategy to widen the interval (between the two shots) to six weeks, 42 days, or more. ”

But vaccine task force coordinator Francisco Ramos is standing firm: “The technical commission recommended this, but we don’t accept it”, he told the paper. “The majority of countries are following the 21-day interval (indicated by manufacturers Pfizer) and we are awaiting evaluation by EMA (the European Medicines Agency)”.

EMA it has to be said has been put in a difficult spot.

The UK, for example, has unilaterally decided to widen the time period between shots to 12 weeks and is going ‘full speed ahead’ faster than any other large nation in the world.

But Pfizer hasn’t given the strategy its blessing. Indeed the company has told Público: “There is no data at this point that shows that protection after the first dose is maintained after 21 days without administration of the second dose”.

Experts will argue that this is because Pfizer’s Phase 3 trials were working against the clock so wanted to keep time-limits short.

But no data, is no data. 

After experts at the World Health Organisation recommended second doses be given by 21 to 28 days – but ‘in exceptional circumstances this interval should be extended to a maximum of six weeks, EMA seemed to go along with it.

But the agency issued a “clarification” two days ago: “The product information (section 4.2 and package leaflet) now recommends the administration of the second dose 3 weeks after the first dose. Previously, the product information stated that the interval should be “at least 21 days”.

“The product information (section 5.1) already states that the participants whose data was used to calculate efficacy received their second dose within 19 to 42 days after their first dose. A sentence has been added with the information that 93.1% of these participants received the second dose 19 to 23 days after the first dose.

There are currently no clinical data on the efficacy of the vaccine when administered beyond intervals used in the clinical trial”.

Now beyond UK a number of other countries have already ‘moved the goal posts’ in terms of administering their second shots.

Says Público, “Denmark already allows it, so does Belgium and Germany. The United States and Canada are some of the others pondering this interval”.

With the whole issue of vaccine supply currently inflaming Europe, it is worth remembering that all the products on the market have only been given ‘emergency use authorisation’.

Their manufacturers are covered by disclaimers protecting them from being sued in the event that any issues arise ‘further down the line’.

In other words, Pfizer technically should have nothing to lose by sanctioning extensions on the time period taken between shots – yet it still decides not to.

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