Moderna Spikevax™ (Red Cap)

≥ 6 Years (100 mcg / 0.5 mL)

This information applies only to Moderna Spikevax™ (Red Cap) to provide doses of 50 mcg or 100 mcg to individuals 6 years and older. Refer to Moderna Spikevax™ (Royal Blue Cap; 25 mcg) for use in those ≥ 6 months to < 6 years of age.
Product Monograph
  • Individuals 6 years of age and older

NOTE: If any interval is longer than recommended, there is no reason to restart the series. Provide the next dose as soon as possible.

Primary Series
  • 12 years and older: 2* x 0.5 mL (100 mcg) doses given IM (deltoid)
  • ≥ 6 years to < 12 years: 2* x 0.25 mL (50 mcg) doses given IM (deltoid)  
    • The 2nd dose should be given at least 28 days after the 1st, which is the Health Canada approved interval.
      • The Ministry of Health recommends an 8-week interval; however 28 days is acceptable.
      • NACI advises an interval of at least 8 weeks between the 1st and 2nd doses is optimal.
        • Local transmission of the SARS-CoV-2 virus; the degree of individual risk of exposure to the virus; and the need of a second dose for earlier protection should be considered when deciding the interval.
        • Individuals who completed their primary vaccine series using manufacturer-authorized intervals also have very good protection against severe COVID-19 disease and do not need to restart their vaccine series.
      • Based on NACI recommendation, the minimum interval is 21 days between doses 1 and 2 (any doses provided at an earlier interval would be considered invalid and need to be repeated).
        • This interval is not a recommended interval and should only be used to determine dose validity.
*Moderately to severely immunocompromised individuals should receive 3 doses for the primary series with an interval of 4 to 8 weeks between all doses.

Booster Doses

Table: Moderna Spikevax™ Booster Doses

Residents of Long-Term Care (Special Care Homes), Personal Care Homes and Seniors’ Assisted Living, regardless of age 0.5 mL (100 mcg mRNA)
Individuals 70 years and older
Moderately to severely immunocompromised individuals
(those who received a 3-dose primary series)
All others eligible for booster dose 0.25 mL (50 mcg mRNA)

Children ≥ 5 years to < 12 years are eligible for booster doses but only with Pfizer-BioNTech Comirnaty™ 10 mcg (Orange Cap). Moderna Spikevax™ is not to be used for booster doses in children < 12 years.

See COVID-19 Vaccine Doses, Eligibility, and Intervals for more details.

Adverse Events
  • Only short-term data are available at this time. Surveillance will continue for long-term adverse events. 
  • Reported adverse events were mild or moderate, more common following the 2nd dose, and generally resolved within 2-3 days.
  • Common adverse events included: 
    • pain, redness, swelling at the injection site
    • fatigue
    • headache
    • myalgia
    • chills
    • nausea or vomiting (children 6 to 11 years)
  • Rare Adverse Events
    • Myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the tissue surrounding the heart) following vaccination with COVID-19 vaccines have been reported in a small number of people. Most cases followed vaccination with mRNA COVID-19 vaccine.
      • Symptoms can include chest pain, shortness of breath, or palpitations (feelings of having a fast-beating, fluttering or pounding heart). In many cases, these conditions are mild and require little to no treatment. However, more severe cases can lead to heart muscle damage.
      • Health Canada has issued a statement regarding updates to Pfizer-BioNTech Comirnaty™ and Moderna Spikevax™ labels.
      • There were no cases of myocarditis or pericarditis reported in the study for children 6 to 11 years old.
        • Myocarditis and pericarditis are rare adverse events so would not be expected to be discovered in this study of ~4000 children. Monitoring real-world conditions will continue.
        • The risk of myocarditis and pericarditis has been higher among individuals 12 to 29 years who received Moderna Spikevax™ (100 mcg or 50 mcg booster) compared to those who received Pfizer-BioNTech Comirnaty™ 30 mcg.
        • The risk of myocarditis and pericarditis seems to be much lower among male children 5 to 11 years who received Comirnaty™ 10 mcg compared to male adolescents who received Comirnaty™ 30 mcg.
        • Until more data are available, NACI preferentially recommends Pfizer-BioNTech Comirnaty™ (Orange Cap) 10 mcg over Moderna Spikevax™ (Red Cap) 50 mcg for children ≥ 6 years to < 12 years. Moderna Spikevax™ 50 mcg should be given if Pfizer-BioNTech Comirnaty™ (Orange Cap) 10 mcg is not available or is contraindicated (e.g. severe allergy to a component).
    • Bell’s palsy / facial paralysis was reported in three recipients in the vaccine group compared to one in the placebo group in the clinical trial. It typically presents as sudden weakness or paralysis on one side of the face and generally starts to improve within a few weeks.
Drug Interactions
  • Anti-SARS-CoV-2 Monoclonal Antibodies
    • For treatment of COVID-19 (e.g., sotrovimab)
      • Based on expert opinion, vaccination with COVID-19 vaccine should be delayed for at least 90 days after treatment with anti-SARS-CoV-2 monoclonal antibodies for treatment of COVID-19 infection, as this therapy may interfere with and delay response to the COVID-19 vaccine. The period of 90 days is based on the half-life of the therapy.
    • For pre-exposure prophylaxis of COVID-19
      • Evusheld™ (tixagevimab / cilgavimab) 
        • NACI recommends delaying administration of Evusheld™ for at least 14 days following COVID-19 vaccination.
        • Information regarding effect of Evusheld™ on future COVID-19 vaccination is not available and NACI recommends timing be assessed on a case-by-case basis in consultation with clinical experts.
Last Updated

06 Sep 2022

  • Individuals 6 to 30 years of age
    • NACI recommends preferential use of the age-appropriate Pfizer-BioNTech Comirnaty™ formulation in these individuals due to potentially lower risk of myocarditis and pericarditis. NACI recommends Moderna Spikevax™ be used as an alternative.
      • For more information see Rare Adverse Events under the tab “What are the indications, dose, adverse events and drug interactions?”
    • There are no data of risk of myocarditis or pericarditis in young children. In Saskatchewan, Pfizer-BioNTech Comirnaty™ is preferred in individuals 12 to 29 years of age.

  • Serious adverse or allergic reaction to previous dose of COVID-19 vaccine unless determined safe by an allergist or other healthcare provider.
    • It is possible for individuals who experienced a severe immediate allergic reaction (e.g. anaphylaxis) after a first dose of an mRNA COVID-19 vaccine to safely receive future doses of the same or another mRNA COVID-19 vaccine in a controlled setting after consulting with an allergist or another appropriate physician if risk assessment deems benefits outweigh risks for the individual and informed consent is provided.
    • Individuals with a history of severe immediate allergic reaction following a dose of an mRNA COVID-19 vaccine should:
      • Consult with an allergist or another appropriate physician before receiving future doses of an mRNA COVID-19 vaccine;
      • Receive future doses of an mRNA COVID-19 vaccine in a controlled setting with someone who is experienced in managing anaphylaxis; and
      • Be observed for at least 30 minutes after vaccination (the normal observation period for people who have not experienced a severe immediate allergic reaction after vaccination is 15 minutes).

  • Reported hypersensitivity to one of the ingredients. See product monograph for ingredients.
    • In individuals with a confirmed severe immediate allergic reaction (e.g., anaphylaxis) to a component of this vaccine or its container, consultation with an allergist is recommended before receiving the vaccine.
    • Polyethylene glycol (PEG) and tromethamine are potentially allergenic ingredients.

  • Currently feeling unwell with symptoms that could be COVID-19 infection so as to: 
    • avoid confusion if symptoms worsen as they could be adverse events of the vaccine or because of the underlying infection; and
    • prevent potential transmission to others who are at the vaccine clinic/site (individuals should be encouraged to follow public health self-isolation recommendations).

  • History of Myocarditis or pericarditis
    • History of myocarditis or pericarditis following mRNA COVID-19 vaccination
      • As a precautionary measure, further doses of mRNA COVID-19 vaccine should be deferred in most individuals who developed myocarditis (with or without pericarditis) within 6 weeks of receiving a previous dose of an mRNA COVID-19 vaccine. This includes any individual who had an abnormal cardiac investigation including electrocardiogram (ECG), elevated troponins, echocardiogram or cardiac MRI after a dose of mRNA vaccine.
      • Those with a history of pericarditis following a dose of mRNA COVID-19 vaccine and who either had no cardiac workup or had normal cardiac investigations can be revaccinated once they are symptom free and at least 90 days has passed since previous COVID-19 vaccine dose.
      • Among those with confirmed myocarditis (with or without pericarditis) following a dose of mRNA COVID-19 vaccine:
        • Administration of subsequent dose(s) of an mRNA COVID-19 vaccine may be considered in certain circumstances upon consultation with the individual’s specialist(s). Considerations for subsequent dose administration may include personal risk of severe acute COVID-19 (e.g., age, underlying conditions) as well as level of COVID-19 community transmission and personal risk of infection.
          • These individuals should be informed of the unknown risk of recurrence of myocarditis and pericarditis following a subsequent mRNA COVID-19 vaccine dose.
          • If vaccination with a dose of mRNA COVID-19 vaccine is chosen, they should wait at least until their episode of myocarditis or pericarditis has completely resolved. This includes resolution of symptoms attributed to myocarditis or pericarditis, as well as no evidence of ongoing heart inflammation or sequelae as determined by the individual's clinical team.
      • Individuals should be advised to seek medical attention if they develop symptoms including chest pain, shortness of breath or palpitations.

    • History of myocarditis or carditis unrelated to mRNA COVID-19 vaccination
      • This is not a contraindication to being immunized with Moderna Spikevax™ (Red Cap).

  • History of multisystem inflammatory syndrome (MIS) in children/adolescents (MIS-C) or adults (MIS-A)
    • MIS-C and MIS-A have very rarely been reported following mRNA COVID-19 vaccination; however, causality has not been established.
    • MIS-C has been reported as a complication of COVID-19 infection; real world evidence among adolescents 12 to 18 years of age suggests vaccination with age-appropriate mRNA vaccine reduces the risk of hospitalization due to MIS-C.
    • COVID-19 vaccination in individuals with a history of MIS-C or MIS-A should be delayed until clinical recovery or until ≥ 90 days since diagnosis, whichever is longer.
  • NOTE: Certain populations were excluded from the initial vaccine trials including pregnancy, breastfeeding, immunocompromised/immunosuppressed, and autoimmune conditions.

    • Based on real world data indicating COVID-19 vaccines are safe in these populations, NACI’s recommendations for COVID-19 vaccination in these populations are now the same as those for the general adult population, which is to receive a complete series of mRNA vaccine and to complete a series initiated with AstraZeneca Vaxzevria™ with mRNA vaccine.   

    • Those who are  immunocompromised have shown lower immune responses to the COVID-19 vaccines compared to those who are immunocompetent. These individuals will need to continue to take precautions against SARS-CoV-2 infection even if fully vaccinated.
      • Moderna Spikevax™ may potentially offer a greater immune response compared to Pfizer-BioNTech Comirnaty™, though Comirnaty™ is preferred for those under 30 years old.
    • Those with autoimmune conditions have shown similar safety and immune response compared to those without autoimmune conditions. Those taking immunosuppressive therapy showed diminished immune response (see above bullet).

    • Regarding pregnancy, the emerging safety and immunogenicity data of COVID-19 vaccines have found:
      • No maternal or neonatal safety signals have been raised. These data have been derived from:
        • international immunization registries
        • preliminary analyses of > 35,000 pregnant women in the US who received mRNA vaccine
      • Data are available indicating mRNA vaccination in pregnant individuals results in comparable antibody titres to those generated following mRNA vaccination in non-pregnant individuals.
      • Maternal IgG humoral response to mRNA COVID-19 vaccines transfers across the placenta to the fetus, leading to a significant and potentially protective, antibody titre in the neonatal bloodstream one week after the second dose.

  • Regarding breastfeeding, the emerging safety data of COVID-19 vaccinations have found:
    • both anti-spike IgG and IgA are present in breastmilk after maternal vaccination with mRNA vaccines
    • mRNA from COVID-19 vaccines was undetectable in breastmilk 4-48 hours post-vaccination in one small cohort study 
Last Updated

06 Sep 2022

Current Infection
  • Individuals with current infection should not present for vaccination to prevent transmission to others at the vaccination clinic/site and should follow public health self-isolation recommendations.
Past Infection
  • If acute symptoms have resolved, the individual can be vaccinated. Following self-isolation recommendations is suggested. 
  • NACI has suggested intervals between SARS-Co-V-2 infection and COVID-19 vaccination.
    • Note that these are suggested, not required intervals. These intervals have not been recommended in Saskatchewan, but there are also no recommendations in Saskatchewan against these longer intervals.
    • Based on vaccine and immunology principles, longer intervals between infection and vaccination are expected to produce more robust and durable responses to the vaccine.
    • See table below for suggestions.

NACI Suggested Intervals Between Previous SARS-CoV-2 Infection and Vaccination with Moderna Spikevax™

SARS-CoV-2 Infection timing relative to COVID-19 vaccination


Suggested interval between SARS-CoV-2 infection and vaccination

Infection prior to initiation or completion of primary vaccination series

(Primary series for individuals moderately to severely immunocompromised is 3 doses)



No previous history of MIS-C or MIS-A following vaccination

Not moderately to severely immunocompromised

Vaccine dose 8 weeks after symptom onset or positive test (if asymptomatic)

No previous history of MIS-C or MIS-A following vaccination

Moderately to severely immunocompromised

Vaccine dose 4-8 weeks after symptom onset or positive test (if asymptomatic)

Previous history of MIS-C or MIS-A following vaccination

Regardless of immunocompromised status

Vaccine dose when recovered clinically or at least 90 days since onset of MIS-C or MIS-A, whichever is longer

Infection after primary series but before booster dose

Individuals 12 years and older currently eligible for a booster dose

3 months after symptom onset or positive test (if asymptomatic) so long as at least 6 months from completing primary series

MIS-A = multisystem inflammatory syndrome in adults; MIS-C = multisystem inflammatory syndrome in children

Last Updated

22 Jun 2022