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AstraZeneca COVID-19 vaccine has been approved, but for how long and with what risks? – The Globe and Mail

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The dearth of data on seniors in AstraZeneca’s earlier trials is one of the reasons Canada’s NACI briefly recommended the shot not be given to people 65 or older, a decision it reversed in mid-March.

HANNIBAL HANSCHKE/Reuters

Join the Globe’s health columnist André Picard and deputy national editor Nicole MacIntyre for a Facebook Live on COVID-19 vaccines on Thursday, April 1 at 2 p.m. Send us your questions. RSVP on Facebook.

When Canada’s National Advisory Committee on Immunization announced on Monday that it was changing its guidance on the AstraZeneca vaccine for the third time in less than a month, chair Caroline Quach-Thanh conceded the rollout of the shot has been, “like a roller coaster.” Here is the latest, including what you need to know if you’re offered the AstraZeneca vaccine.

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Tracking Canada’s COVID-19 vaccine rollout plans: A continuing guide

Coronavirus tracker: How many COVID-19 cases are there in Canada and worldwide? The latest maps and charts

Here is the latest, including what you need to know if you’re offered the AstraZeneca vaccine.

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Why has Canada paused use of the AstraZeneca vaccine for people under the age of 55?

NACI recommended the pause after more data emerged from Europe over the weekend of March 27 and 28 suggesting that an extremely rare and potentially deadly clotting disorder may be linked to the AstraZeneca vaccine.

In mid-March, more than a dozen European countries temporarily halted use of the shot after a handful of baffling adverse events, some of them fatal, were identified in patients who had recently received the jab. Unlike common clotting disorders, these cases involved low platelet counts and, in some instances, dangerous clots in a vein in the brain.

European and British drug regulators investigated, and on March 18 they released parallel reports that found no direct link between blood clots and the AstraZeneca vaccine. Canada continued to support the vaccine during the investigations, never suspending its use.

So what changed over the last weekend of March? New German-led research, published online and still undergoing peer review, found the post-vaccination clots were comparable to those caused by a disorder that is known to sometimes occur in reaction to the blood thinner heparin.

In all of the four post-vaccination cases for which the research team had access to blood samples, a test identified antibodies similar to those found in people suffering from the heparin-induced version of the illness. The study team dubbed the new version vaccine-inducted prothrombotic immune thrombocytopenia, or VIPIT. It’s important to note, however, that other experts have argued the German research doesn’t definitively prove the vaccine is to blame.

With scientists having described a plausible mechanism that could link the AstraZeneca shot to the rare clotting disorder, NACI decided to take action. The chief medical officers of health for every province and territory met virtually on Sunday night and agreed to follow NACI’s advice.

Why has the age cut-off been set at 55?

There are two reasons, both having to do with risk. So far, VIPIT cases in people older than 55 have been extremely rare, despite most of the tens of millions of AstraZeneca doses injected in Europe and Britain going into the arms of seniors.

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The risk of serious illness and death due to COVID-19, on the other hand, rises sharply with age. Shelley Deeks, the vice-chair of NACI, told a news conference Monday that it made sense to keep giving the AstraZeneca shot to the population most in danger from the virus, especially with more lethal variants spreading and the third wave escalating.

For people younger than 55, the calculation is more complex. At first, regulators in Europe estimated the risk of the syndrome now known as VIPIT at one case per million vaccinations, Dr. Deeks explained. “As the time has progressed, we’ve seen more cases that have been identified in Europe and the rate has been identified as 1 per 100,000 in Germany,” Dr. Deeks said. “Where the true rate is, we just don’t know at this point in time.”

Of the VIPIT cases that have been identified so far, 40 per cent have been fatal. Given that, Dr. Deeks said NACI decided to err on the side of caution and direct younger people to the mRNA vaccines made by Pfizer-BioNTech and Moderna, neither of which have been associated with the clotting disorder. The mRNA vaccines make up the vast majority of Canada’s supply.

Most cases of the rare clotting disorder have been found in women. Why isn’t Canada giving the AstraZeneca vaccine to men under 55?

It’s unclear why most of the known cases of VIPIT have occurred in women. It could be because more young women than young men received the AstraZeneca vaccine. Most of the early young recipients were health care workers, a profession that skews female.

“While these reported adverse events have occurred primarily in women, investigations are ongoing as it is possible that more women received the AstraZeneca vaccine, making it difficult to assess risk based on sex,” said Howard Njoo, Canada’s deputy chief public health officer.

Health Canada hasn’t changed the label on the vaccine to match NACI’s advice. Why not?

Supriya Sharma, Health Canada’s chief medical adviser, said the regulator is still investigating. Health Canada has asked AstraZeneca to provide a new risk-benefit analysis for the shot, broken down by age group and gender.

On March 24, Health Canada updated the product monograph – the vaccine’s official label – to provide information on the very rare risk of clots potentially associated with the shot. The changes apply to both the regular AstraZeneca product and a nearly identical product made in India, known as Covishield.

Dr. Sharma pointed out that other regulators, including the European Medicines Agency, have not changed the label regarding age either, even though public-health officials in some European countries have made recommendations similar to NACI’s. France is recommending it for people 55 and older, and Sweden for those 65 and up. Norway, Denmark and Finland, meanwhile, have suspended use of the AstraZeneca vaccine for all ages.

How has the AstraZeneca vaccine performed in the real world?

Very well. Developed in partnership with Oxford University, the AstraZeneca jab has been the workhorse of Britain’s successful vaccination drive. As a result, the bulk of the real-world data on the shot’s effectiveness come from Britain.

Public Health England continues to publishes regular updates on how effective COVID-19 vaccines are proving, and the AstraZeneca shot has helped to cut cases, hospital admissions and deaths significantly, including those caused by the B.1.1.7 variant, a version of the coronavirus that is now spreading quickly in Canada.

One notable exception arose in South Africa, where the government halted use of the vaccine when preliminary results showed it wasn’t making much of a difference in preventing mild disease. Like other vaccines, the AstraZeneca shot doesn’t work as well against B.1.351, the dominant variant in South Africa, as it does against B.1.1.7 and earlier versions of the coronavirus.

16/16

14/14

11/11

How the oxford-AstraZeneca

vaccine works

The Oxford University and AstraZeneca COVID-19

vaccine is highly effective at preventing people

contracting coronavirus when it is administered as

a half dose followed by a full dose at least

one month later.

Spike

protein

Spike protein:

Gene is cut from

Sars-CoV-2 genome

Virus

genome

Gene: Inserted into DNA

of adenovirus which acts

as vector in vaccine

Adenovirus:

Unable to

cause disease

Vaccine: Induces spike

protein antigen – triggers

antibody immune response

Antibodies

Human immune

system: Produces

antibodies against

spike proteins

Vaccine: Can be

stored in refrigerator

at 2 to 8°C. Two doses

of vaccine are

required

graphic news, SOURCE: Reuters; Oxford

Vaccine Trial; University of Oxford

16/16

14/14

11/11

How the oxford-AstraZeneca

vaccine works

The Oxford University and AstraZeneca COVID-19 vaccine

is highly effective at preventing people contracting coronavirus

when it is administered as a half dose followed by a

full dose at least one month later.

Spike

protein

Spike protein:

Gene is cut from

Sars-CoV-2 genome

Virus

genome

Gene: Inserted into DNA

of adenovirus which acts

as vector in vaccine

Adenovirus:

Unable to

cause disease

Vaccine: Induces spike

protein antigen – triggers

antibody immune response

Antibodies

Human immune

system: Produces

antibodies against

spike proteins

Vaccine: Can be

stored in refrigerator

at 2 to 8°C. Two doses

of vaccine are

required

graphic news, SOURCE: Reuters; Oxford Vaccine Trial;

University of Oxford

18/18

16/16

13/13

How the oxford-AstraZeneca vaccine works

The Oxford University and AstraZeneca COVID-19 vaccine is highly effective

at preventing people contracting coronavirus when it is administered

as a half dose followed by a full dose at least one month later.

Spike protein

Adenovirus:

Unable to

cause disease

Virus genome

Spike protein:

Gene is cut from

Sars-CoV-2 genome

Gene: Inserted into DNA

of adenovirus which acts

as vector in vaccine

Antibodies

Vaccine: Induces spike

protein antigen – triggers

antibody immune response

Human immune

system: Produces

antibodies against

spike proteins

Vaccine: Can be

stored in refrigerator

at 2 to 8°C. Two doses

of vaccine are required

graphic news, SOURCE: Reuters; Oxford Vaccine Trial; University of Oxford

Why hasn’t the U.S. approved the AstraZeneca shot?

Before the U.S. Food and Drug Administration would consider approval, the regulator asked the company to conduct a larger clinical trial primarily in the United States, one that enrolled more seniors than did AstraZeneca’s earlier trials. (The dearth of data on seniors in AstraZeneca’s earlier trials is one of the reasons Canada’s NACI briefly recommended the shot not be given to people 65 or older, a decision it reversed in mid-March.)

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Controversy erupted when AstraZeneca finally released the results of the U.S. trial last week.

In a press release March 22, the British-Swedish company said the trial, which enrolled more than 32,000 participants in the U.S., Chile and Peru, found two doses of the vaccine given four weeks apart to be 79-per-cent efficacious against symptomatic disease and 100-per-cent efficacious in preventing COVID-19 hospital admissions and deaths.

Less than 24 hours later, the U.S. National Institute of Allergy and Infectious Diseases issued an extraordinary middle-of-the-night statement saying the independent scientists monitoring the trial were concerned the data in the press release were outdated and possibly misleading. AstraZeneca revised its conclusions two days later to say the vaccine was 76-per-cent efficacious against symptomatic COVID-19.

Company officials are expected to receive a grilling when they appear before an FDA advisory committee that makes recommendations on vaccine approvals. A date for the meeting, a precursor to approval, has not yet been set.

What will happen to Canada’s AstraZeneca supply, including a new shipment of 1.5 million doses from the U.S.?

Provinces are continuing to roll out the vaccine to people 55 and over, and they plan to do the same with doses that arrived from the U.S. Tuesday as part of a loan arrangement. NACI, Health Canada and chief medical officers of health for every province all say the benefits of the shot continue to outweigh the risks for older people.

The same advice applies to Covishield, which is so far the only version of the AstraZeneca shot to be injected in Canada. The federal government received 500,000 doses of the product from India in March; a little over 300,000 of those have been injected so far.

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If I’m younger than 55 and I’ve already received a first dose of AstraZeneca, what should I do about my second shot?

Wait for advice from NACI and Health Canada. Dr. Njoo said Monday that more definitive information should be available by the time recipients are due for their second doses, which NACI has advised be given as far apart as four months as part of a “first doses fast” strategy.

There is a possibility that Canadians may be permitted to mix and match their first and second doses, but that depends on the results of international trials. Britain is studying a mix-and-match strategy. Findings could be available as early as June or July, Dr. Sharma said.

If I do decide to take the AstraZeneca vaccine, how can I monitor myself for signs of VIPIT?

VIPIT is so rare that no cases of it have yet been identified in Canada. Based on Europe’s limited experience, Health Canada has advised vaccine recipients and their doctors to watch out for any of the following symptoms four to 16 days after receiving the shot: Shortness of breath, chest pain, leg swelling, persistent abdominal pain, sudden onset of severe and worsening headaches, and skin bruising in places other than the injection site. McMaster University in Hamilton is prepared to test for the syndrome, which can be successfully treated if caught in time.

The large number of COVID-19 infections in some places makes it more likely for new variants of the virus to emerge. Science Reporter Ivan Semeniuk explains how vaccines may not be as effective against these new strains, making it a race to control and track the spread of variants before they become a dangerous new outbreak. The Globe and Mail

With a report from Ivan Semeniuk

Our Morning Update and Evening Update newsletters are written by Globe editors, giving you a concise summary of the day’s most important headlines. Sign up today.

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Almost half of Shopify’s top execs to depart company: CEO

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By Moira Warburton

(Reuters) – Three of e-commerce platform Shopify’s seven top executives will be leaving the company in the coming months, chief executive officer and founder of Canada‘s most valuable company Tobi Lutke said in a blog post on Wednesday.

The company’s chief talent officer, chief legal officer and chief technology officer will all transition out of their roles, Lutke said, adding that they have been “spectacular and deserve to take a bow.”

“Each one of them has their individual reasons but what was unanimous with all three was that this was the best for them and the best for Shopify,” he said.

The trio follow the departure of Craig Miller, chief product officer, in September. Lutke took on the role in addition to CEO.

Shopify, which provides infrastructure for online stores, has seen its valuation soar in the last year as many businesses went virtual during COVID-19 lockdowns. It has a market cap valuation of C$182.7 billion ($146 billion), above Canada‘s top lender Royal Bank of Canada.

It is Canada‘s biggest homegrown tech success story, founded in 2006 and supporting over 1 million businesses globally, according to the company.

“We have a phenomenally strong bench of leaders who will now step up into larger roles,” Lutke said, but did not name replacements.

Shopify said in February revenue growth would slow this year as vaccine rollouts encourage people to return to stores and warned it does not expect 2020’s near doubling of gross merchandise volume, an industry metric to measure transaction volumes, to repeat this year.

Chief talent officer, Brittany Forsyth, was the 22nd employee hired at Shopify and has been with the company for 11 years. She said on Twitter that post-Shopify she would be focusing on Backbone Angels, an all-female collective of angel investors she co-founded in March.

Shopify shares fell 5.1% while the benchmark Canadian share index ended marginally down.

($1 = 1.2515 Canadian dollars)

 

(Reporting by Moira Warburton in Toronto; Editing by Aurora Ellis)

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CANADA STOCKS – TSX falls 0.14% to 19,201.28

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* The Toronto Stock Exchange’s TSX falls 0.14 percent to 19,201.28

* Leading the index were Stantec Inc <STN.TO​>, up 3.4%, Imperial Oil Ltd​, up 3.3%, and Corus Entertainment Inc​, higher by 2.9%.

* Lagging shares were Aphria Inc​​, down 14.2%, Village Farms International Inc​, down 9.9%, and Aurora Cannabis Inc​, lower by 9.4%.

* On the TSX 91 issues rose and 134 fell as a 0.7-to-1 ratio favored decliners. There were 24 new highs and no new lows, with total volume of 228.0 million shares.

* The most heavily traded shares by volume were Toronto-dominion Bank, Royal Bank Of Canada and Suncor Energy Inc.

* The TSX’s energy group fell 0.32 points, or 0.3%, while the financials sector climbed 2.46 points, or 0.7%.

* West Texas Intermediate crude futures rose 0.52%, or $0.31, to $59.63 a barrel. Brent crude  rose 0.4%, or $0.25, to $63.2 [O/R]

* The TSX is up 10.1% for the year.

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Air Canada signs C$5.9 billion government aid package, agrees to buy Airbus, Boeing jets

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By David Ljunggren and Allison Lampert

OTTAWA/MONTREAL (Reuters) -Air Canada, struggling with a collapse in traffic due to the COVID-19 pandemic, reached a deal on Monday on a long-awaited aid package with the federal government that would allow it to access up to C$5.9 billion ($4.69 billion) in funds.

The agreement – the largest individual coronavirus-related loan that Ottawa has arranged with a company – was announced after the airline industry criticized Prime Minister Justin Trudeau’s Liberal government for dawdling. The United States and France acted much more quickly to help major carriers.

Canada‘s largest carrier, which last year cut over half its workforce, or 20,000 jobs, and other airlines have been negotiating with the government for months on a coronavirus aid package.

In February, Air Canada reported a net loss for 2020 of C$4.65 billion, compared with a 2019 profit of C$1.48 billion.

As part of the deal, Air Canada agreed to ban share buybacks and dividends, cap annual compensation for senior executives at C$1 million a year and preserve jobs at the current level, which is 14,859.

It will also proceed with planned purchases of 33 Airbus SE 220 airliners and 40 Boeing Co 737 MAX airliners.

Chris Murray, managing director, equity research at ATB Capital Markets, said the deal took into account the “specific needs of Air Canada in the short and medium term without being overly onerous.”

He added: “It gives them some flexibility in drawing down additional liquidity as needed.”

Transport Minister Omar Alghabra said the government was still in negotiations with other airlines about possible aid.

Canada, the world’s second-largest nation by area, depends heavily on civil aviation to keep remote communities connected.

Opposition politicians fretted that further delays in announcing aid could result in permanent damage to the country.

Air Canada said it would resume services on nearly all of the routes it had suspended because of COVID-19.

‘SIGNIFICANT LAYER OF INSURANCE’

The deal removes a potential political challenge for the Liberals, who insiders say are set to trigger an election later this year.

The government has agreed to buy C$500 million worth of shares in the airline, at C$23.1793 each, or a 14.2% discount to Monday’s close, a roughly 6% stake.

“Maintaining a competitive airline sector and good jobs is crucially important,” Finance Minister Chrystia Freeland told reporters, adding the equity stake would allow taxpayers to benefit when the airline’s fortunes recovered.

The Canadian government previously approved similar loans for four other companies worth up to C$1.billion, including up to C$375 million to low-cost airline Sunwing Vacations Inc. The government has paid out C$73.47 billion under its wage subsidy program and C$46.11 billion in loans to hard-hit small businesses.

Michael Rousseau, Air Canada‘s president and chief executive officer, said the liquidity “provides a significant layer of insurance for Air Canada.”

Jerry Dias, head of the Unifor private-sector union, described the announcement as “a good deal for everybody.”

Unifor represents more than 16,000 members working in the air transportation sector.

But the Canadian Union of Public Employees, which represents roughly 10,000 Air Canada flight attendants, said the package protected the jobs of current workers rather than the 7,500 members of its union who had been let go by the carrier.

($1=1.2567 Canadian dollars)

(Reporting by David Ljunggren in Ottawa and Allison Lampert in Montreal; Additional reporting by Julie Gordon in Ottawa and Munsif Vengattil in Bengaluru; Editing by Dan Grebler and Peter Cooney)

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