Johnson & Johnson’s one-dose COVID-19 vaccine appeared safe and effective in trials, the U.S. Food and Drug Administration said Wednesday, paving the way for its approval for emergency use as soon as this week.
The vaccine was 66 per cent effective at preventing moderate to severe COVID-19 in a 44,000 person global trial, the FDA said in documents ahead of a Friday meeting of independent experts who will advise the agency on emergency authorization.
New data provided by J&J to the FDA showed the vaccine was 64 per cent effective at stopping moderate to severe cases of COVID-19 after 28 days in thousands of trial participants in South Africa where a worrying new variant has swept across the country.
Overall, the vaccine was 100 per cent effective at stopping hospitalization 28 days after vaccination, compared with 85 per cent at 14 days, and there were no COVID-19 deaths among those who received the shot rather than a placebo.
J&J also said the data suggested its vaccine cut down on asymptomatic infections, which experts said was another sign COVID-19 vaccines may indeed stop transmission of the disease.
“Most encouraging to me were the data in South Africa,” said Paul Offit, director of the Vaccine Education Center at the Children’s Hospital of Philadelphia and a member of the FDA advisory committee that will make its recommendation on Friday.
COVID-19 is caused by a virus called SARS-CoV-2, and as it spread around the world, it mutated into new forms that are more quickly and easily transmitted through small water droplets in the air. Canadian health officials are most worried about variants that can slip past human immune systems because of a different shape in the spiky protein that latches onto our cells. The bigger fear is that future mutations could be vaccine-resistant, which would make it necessary to tweak existing drugs or develop a new “multivalent” vaccine that works against many types, which could take months or years.
Not all variants are considered equal threats: Only those proven to be more contagious or resistant to physical-distancing measures are considered by the World Health Organization to be “variants of concern.” Five of these been found in Canada so far. The WHO refers to them by a sequence of letters and numbers known as Pango nomenclature, but in May of 2021, it also assigned them Greek letters that experts felt would be easier to remember.
- Country of origin: Britain
- Traits: Pfizer-BioNTech and Moderna vaccines are still mostly effective against it, studies suggest, but for full protection, the booster is essential: With only a first dose, the effectiveness is only about 66 per cent.
- Spread in Canada: First detected in Ontario’s Durham Region in December. It is now Canada’s most common variant type. Every province has had at least one case; Ontario, Quebec and the western provinces have had thousands.
- Country of origin: South Africa
- Traits: Some vaccines (including Pfizer’s and Oxford-AstraZeneca’s) appear to be less effective but researchers are still trying to learn more and make sure future versions of their drugs can be modified to fight it.
- Spread in Canada: First case recorded in Mississauga in February. All but a few provinces have had at least one case, but nowhere near as many as B.1.1.7.
- Country of origin: Brazil
- Traits: Potentially able to reinfect people who’ve recovered from COVID-19.
- Spread in Canada: B.C. has had hundreds of cases, the largest known concentration of P.1 outside Brazil. More outbreaks have been detected in Ontario and the Prairies.
DELTA (B.1.617 AND B.1.617.2)
- Country of origin: India
- Traits: Spreads more easily. Single-dosed people are less protected against it than those with both vaccine doses.
- Spread in Canada: All but a few provinces have recorded cases, but B.C.’s total has been the largest so far.
- Country of origin: Peru
- Traits: Spreads more easily. Health officials had been monitoring it since last August, but the WHO only designated it a variant of concern in June of 2021.
- Spread in Canada: A handful of travel-related cases were first detected in early July.
If I’m sick, how do I know whether I have a variant?
Health officials need to genetically sequence test samples to see whether it’s the regular virus or a variant, and not everyone’s sample will get screened. It’s safe to assume that, whatever the official variant tallies are in your province, the real numbers are higher. But for your purposes, it doesn’t matter whether you contract a variant or not: Act as though you’re highly contagious, and that you have been since before your symptoms appeared (remember, COVID-19 can be spread asymptomatically). Self-isolate for two weeks. If you have the COVID Alert app, use it to report your test result so others who may have been exposed to you will know to take precautions.
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“That you could still get protection against medically attended illnesses – meaning hospitalization, ICU admission and deaths from that vaccine against the South African strain, I thought that was really encouraging.”
While the FDA is not bound to follow the advice of its experts, it approved both the Pfizer and Moderna vaccines the day after the advisory committee met.
The United States, where COVID-19 has killed more than half a million people, has been struggling to speed up its vaccination program because of the limited supply of the Pfizer-BioNTech and Moderna vaccines so far.
Worldwide, COVID-19 has infected 112 million people and killed more than 2.5 million and governments are racing to get their hands on any effective vaccines.
ASYMPTOMATIC TRANSMISSION CUT
J&J said this week that it expected to have 4 million shots ready to go following an FDA green light and would ship 20 million doses by the end of March. It has promised the United States 100 million doses by the end of June.
The vaccine is administered in a single dose and can be stored in normal fridges, in contrast to the Pfizer and Moderna shots which need two doses and must be kept in freezers.
The J&J vaccine is also considered essential in the global vaccination effort due to its routine storage requirements and is already being rolled out to 500,000 healthcare workers in South Africa.
J&J said in documents submitted to the FDA that in a preliminary analysis of its trial, it found 16 cases of asymptomatic cases in the placebo group versus two in the vaccine group, or an 88 per cent efficacy rate.
While fighting asymptomatic infection was not the primary goal of the trial, which studied the vaccine’s ability to stop moderate to severe COVID-19, the reduction of asymptomatic cases implies the shot can also cut transmission of the disease.
“The data is consistent with the fact that these coronavirus vaccines, including the J&J vaccine, do have an impact which is significant on asymptomatic spread,” said Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security.
However, he said some public health authorities may ask to see more robust data before being persuaded.
The effectiveness of the one-dose vaccine varied over time. In Brazil, where a similar variant to the one in South Africa is circulating, the vaccine was 66 per cent after 14 days, rising to 68 per cent at 28 days. In the United States, the effectiveness fell from 74 per cent at 14 days to 72 per cent two weeks later.
Overall, only two vaccine recipients developed COVID-19 severe enough to need medical intervention after 14 days and that dropped to zero after 28 days.
J&J has said it sees rising immunity from its vaccine until at least 28 days after injection. The drugmaker has said it expects sustained – or even improved – protection over time.
Three vaccine recipients had severe side effects in the trial that were likely related to the vaccine, but the FDA said its analysis did not raise any specific safety concerns that would preclude issuance of an emergency use authorization.
The FDA said the most common reactions were injection site pain at 48.6 per cent, headache at 39 per cent, fatigue at 38.2 per cent and myalgia at 33.2 per cent. Other side effects included a fever in 9 per cent of participants and a high fever in 0.2 per cent of those who received the vaccine.
The regulator said one case of pericarditis, a heart disease, may have been caused by the vaccine. It said cases of a rare disorder, Guillain-Barre Syndrome, were unlikely to be related to the shot though data was insufficient to determine whether the vaccine had caused these side effects.
The Globe and Mail
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