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Pfizer COVID-19 vaccine provisionally approved for Australian use
By Liam Mannix and Craig Butt
The Therapeutic Goods Administration says Australia’s first COVID-19 vaccine will prevent symptomatic COVID-19 in 95 per cent of recipients, but more than half will experience side effects such as headaches and fatigue.
On Monday – exactly a year after Australia confirmed its first case of the virus – the TGA gave provisional approval for the Pfizer COVID-19 vaccine for use in Australia.
But the long-awaited vaccine comes with some side effects which are spelt out in summary documents published by the medical regulator.
According to the TGA, more than 60 per cent of people who get the Pfizer jab will experience fatigue, more than half will get a headache, more than 30 per cent will suffer muscle pain or chills and more than one in five will experience joint pain.
“We know, when you have the vaccine, there is a good chance it’s going to make you feel pretty crook,” said Professor Bruce Thompson, dean of the school of health sciences at Swinburne University.
The side effects dissipate after a few days and set against them is the authority’s finding that the Pfizer vaccine prevents symptomatic COVID-19 in 95 per cent of patients.
A certified medical assistant prepares a dose of the Pfizer-BioNTech COVID-19 vaccine at a vaccination.Credit: AP
The regulator said it was confident the vaccine had an acceptable safety profile – but the short-term side effects are significantly greater than that of the flu shot many Australians get each year.
“These side effects are more common than with say, the influenza vaccine, so people should be mentally prepared for that, particularly after the second dose,” said Professor Julie Leask, a reseacher focussed on vaccine uptake at the University of Sydney.
Importantly, scientists say these side-effects are evidence the vaccine is working, generating a powerful immune response to an invader, just like a cold or the flu.
Two people in Britain suffered anaphylactic shock after the vaccine but both had a history of severe allergic reactions, and both have since recovered.
Data from the vaccine rollout suggests about 11.1 people in every million given the vaccine will experience anaphylaxis. In light of that, the TGA is asking health professionals to closely watch people for at least 15 minutes after injection.
So far, the vaccine trials have tracked participants for only two months. However, the TGA believes nearly all serious vaccine side-effects should show up after four weeks, so they are confident the vaccine has an acceptable level of safety.
Prime Minister Scott Morrison said on Monday morning that the green light was a formal approval under the normal processes of the TGA and not an emergency measure, but warned that the coronavirus crisis was far from over.
“I have a simple message to Australia, thank you Australia,” he said. “Thank you that you have put us in a situation that is the envy of most countries in the world today. We intend to keep it that way. We intend to remain vigilant.
“Once the vaccines start, that doesn’t mean you can jump on a plane to Bali the next day, that the masks or the quarantine arrangements disappear ... this will build, it will start at a small scale but it is not a silver bullet.”
The provisional approval is for individuals over 16 years of age, with two doses required at least 21 days apart. It is a temporary approval to meet public need, where the benefits of early approval outweigh the risks.
For the very frail – people aged over 85 – the TGA recommends doctors and nurses vaccinate on a “case-by-case basis”, as the potential benefits of the vaccine must be weighed against the risks of exposing a very frail person to the vaccine’s side-effects.
About 80,000 doses will be administered every week from late February and the rate will increase once the doses of AstraZeneca’s vaccine to be manufactured in Australia – which will peak at 1 million doses a week – can be distributed. The rollout is expected to be completed by October.
“Around August last year we took the decision that we didn’t want to be in a situation where we were completely reliant on the production of vaccines overseas,” Mr Morrison said. “We put the arrangements in place to ensure we would be able to produce our own vaccine here in Australia and that is happening now.”
He said Australia “paid a premium” for the capabilities and that the federal government was involved more broadly in the development of vaccine production facilities in Melbourne.
“That was the right decision for Australia because, as much as you can, you want to be able to control as many things as you can in this country when dealing with COVID-19.”
Mr Morrison said the logistical challenge of distributing the vaccine in a country as large as Australia would be significant.
“There will be swings and roundabouts in the process,” he said. “You can also expect for us to explain those as they occur.”
Foreign Affairs Minister Marise Payne has started working with Australia’s Pacific island neighbours on preparations to administer the COVID-19 vaccine in the region.
“I have had some fantastic messages back from Pacific leaders over the course of the last week,” Mr Morrison said. “They are appreciative of the proactive role that Australia has taken to ensure that they will be in a position to administer that vaccine.”
Health Minister Greg Hunt said the regulators at the TGA had been working tirelessly to introduce a safe and effective COVID-19 vaccine in Australia.
“The TGA’s processes are, I believe, the best in the world and we have ensured that they are thorough,” Mr Hunt said. “The TGA has placed safety above all else.”
The head of the TGA, Adjunct Professor John Skerritt, thanked the clinical and medical officers, scientists, pharmacists and experts in statistics, laboratory analysis and manufacturing assessment who “have worked tirelessly” on assessing the vaccine.
The vaccine was approved after a phase three trial in which 43,651 people aged over 16 were enrolled.
Of the 36,523 people eligible for the interim analysis, there were 170 confirmed cases of COVID-19 – 162 of them in people given the placebo.
These large numbers allow scientists to be confident in their findings. The TGA’s analyses puts the vaccine’s effectiveness at preventing symptomatic COVID-19 at 95 per cent – or, to put that another way, there is a 97.5 per cent chance the vaccine’s efficacy is at least 90.3 per cent.
Many unknowns
However, there are some unknowns.
It remains unclear if the vaccine will have any effect on reducing the transmission of the virus. It also remains unclear what effect the vaccine has on asymptomatic COVID-19, as people in the trial were only tested for COVID-19 if they had symptoms.
It also remains unclear just how long the vaccine will be effective. In monkeys, declining antibody and immune-cell levels over five weeks were noted.
Health professionals will also need to decide whether to inoculate pregnant women, people with autoimmune disorders and those with compromised immune systems, as the TGA said there is limited human data to guide advice.
What side effects can I expect from Pfizer’s COVID-19 vaccine?
Pfizer’s vaccine is “more reactogenic” – it will cause a variety of short-term side-effects. Scientists say these side-effects are evidence the vaccine is working, generating a powerful immune response to an invader.
According to data published by the Therapeutic Goods Administration on Tuesday, more than 60 per cent of those who get a jab will experience fatigue, more than 50 per cent will get a headache, more than 30 per cent will get muscle pain or chills and more than 20 per cent will have joint pain.
Young people seem slightly more likely to have side-effects than the elderly.
How long do they last?
Most side effects arise two or three days after vaccination, and on average last a single day.
How does that compare with the flu vaccine?
Sequiris’s seasonal flu vaccine is substantially less likely to cause side effects. Its most common side effects are muscle pain and headache, reported by about 20 per cent of people who have the vaccine. But the pain means the COVID-19 jab is working.
“You’re getting the immune system to do something,” said Professor Bruce Thompson, dean of the School of Health Sciences at Swinburne University.
“That’s the whole point of the vaccine.”
Are there any serious or long-term side effects?
Among 37,586 study participants with an average of two months of follow-up data, only three people had serious adverse events linked the vaccine.
One person suffered a shoulder injury, another an abnormal heartbeat, and a third had swollen lymph nodes.
Since the vaccine started rolling out, another rare but serious side effect has been spotted: anaphylactic shock. Two people in Britain suffered anaphylactic shock after the vaccine; both had a history of severe allergic reactions, and both have since recovered.
Data from the vaccine rollout suggests about 11.1 people in every million given the vaccine will experience anaphylaxis. In light of that, the TGA is asking health professionals to closely watch people for at least 15 minutes after injection.
What about the people who died in Norway?
Concerns were raised earlier this month after 33 Norwegians aged over 75 died after receiving the vaccine. Health authorities there have not drawn a direct link between the vaccine and the deaths.
While the vaccine has been trialled on people over 65, there is only limited data available on its effect on people who are over 85. For this reason, the TGA has recommended they be vaccinated on a case-by-case basis, if health professionals feel the risk outwights the benefits.
“People over 85 might have multiple medical problems. To make it a blanket rule to say ‘it’s perfectly fine’ when someone might have problems with their heart, renal disease, it’s not straightforward,” said Professor Thompson.
“You’re asking someone with a whole sway of medical problems, you’re putting their immune system under stress.“
What about pregnant women?
There is only limited data on giving the vaccine to pregnant women. While animal studies do not suggest any risks, at this stage the TGA advises the vaccine “should only be considered when the potential benefits outweigh any potential risks for the mother and fetus”.