The drug company Moderna has begun a study that will test its COVID-19 vaccine in children younger than 12, including babies as young as 6 months, the company said Tuesday.
The study is expected to enroll 6,750 healthy children in the United States and Canada. Moderna declined to say how many had already signed up or received the first shots, according to a spokeswoman, Colleen Hussey.
“There’s a huge demand to find out about vaccinating kids and what it does,” said Dr. David Wohl, medical director of the vaccine clinic at the University of North Carolina, who is not involved in the study.
In a separate study, Moderna is testing its vaccine in 3,000 children ages 12-17 and may have results for that age group by summer. The vaccine would then have to be authorized for use in children, so it would not be immediately available.
Many parents want protection for their children, and vaccinating children should help to produce the herd immunity considered crucial to stopping the pandemic. The American Academy of Pediatrics has called for expansion of vaccine trials to include children.
Canada pre-purchased millions of doses of seven different vaccine types, and Health Canada has approved four so far for the various provincial and territorial rollouts. All the drugs are fully effective in preventing serious illness and death, though some may do more than others to stop any symptomatic illness at all (which is where the efficacy rates cited below come in).
- Also known as: Comirnaty
- Approved on: Dec. 9, 2020
- Efficacy rate: 95 per cent with both doses in patients 16 and older, and 100 per cent in 12- to 15-year-olds
- Traits: Must be stored at -70 C, requiring specialized ultracold freezers. It is a new type of mRNA-based vaccine that gives the body a sample of the virus’s DNA to teach immune systems how to fight it. Health Canada has authorized it for use in people as young as 12.
- Also known as: SpikeVax
- Approved on: Dec. 23, 2020
- Efficacy rate: 94 per cent with both doses in patients 18 and older, and 100 per cent in 12- to 17-year-olds
- Traits: Like Pfizer’s vaccine, this one is mRNA-based, but it can be stored at -20 C. It’s approved for use in Canada for ages 12 and up.
- Also known as: Vaxzevria
- Approved on: Feb. 26, 2021
- Efficacy rate: 62 per cent two weeks after the second dose
- Traits: This comes in two versions approved for Canadian use, the kind made in Europe and the same drug made by a different process in India (where it is called Covishield). The National Advisory Committee on Immunization’s latest guidance is that its okay for people 30 and older to get it if they can’t or don’t want to wait for an mRNA vaccine, but to guard against the risk of a rare blood-clotting disorder, all provinces have stopped giving first doses of AstraZeneca.
- Also known as: Janssen
- Approved on: March 5, 2021
- Efficacy rate: 66 per cent two weeks after the single dose
- Traits: Unlike the other vaccines, this one comes in a single injection. NACI says it should be offered to Canadians 30 and older, but Health Canada paused distribution of the drug for now as it investigates inspection concerns at a Maryland facility where the active ingredient was made.
How many vaccine doses do I get?
All vaccines except Johnson & Johnson’s require two doses, though even for double-dose drugs, research suggests the first shots may give fairly strong protection. This has led health agencies to focus on getting first shots to as many people as possible, then delaying boosters by up to four months. To see how many doses your province or territory has administered so far, check our vaccine tracker for the latest numbers.
Vaccine side effects such as fever, sore arms, fatigue and achy joints and muscles can be more intense in children than in adults, and doctors say it is important for parents to know what to expect after their children are inoculated.
Canada vaccine tracker: How many COVID-19 doses have been administered so far?
Moderna developed its vaccine in collaboration with the National Institute of Allergy and Infectious Diseases. The company and the institute are also working together on the study, along with the federal Biomedical Advanced Research and Development Authority.
The children will be followed for a year, to look for side effects and measure antibody levels that will help researchers determine whether the vaccine appears to provide protection. The antibody levels will be the main indicator, but the researchers will also look for coronavirus infections, with or without symptoms.
Johnson & Johnson has also said it would test its coronavirus vaccine in babies and young children after testing it first in older children.
Pfizer and BioNTech are testing their vaccine in children ages 12-15 and have said the plan is to move to younger groups; the product is already authorized for use in those 16 and older in the United States.
Last month, AstraZeneca began testing its vaccine in Britain in children 6 years and older.
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