Product Information

Vaxzevria™ COVID-19 Vaccine (AstraZeneca) - product monograph

Indication

  • Individuals 18 year and older

Dose

  • 2x 0.5 ml doses given IM (preferably deltoid)
  • The 2nd dose should be given between 4 and 12 weeks after the 1st.
  • NACI advises that intervals up to 16 weeks may be required in the context of vaccine supply constraints.
    • If the 2nd dose is delayed beyond 16 weeks, there is no reason to restart the series. Provide the 2nd dose as soon as possible as both doses are needed for full immune protection. 

Adverse Effects

  • Only short to medium term data are available at this time. Surveillance will continue for long-term adverse effects.
  • The most commonly reported adverse effects included:  
    • injection site tenderness
    • injection site pain
    • fatigue
    • headache
    • myalgia
    • malaise
    • pyrexia
    • chills
    • arthralgia
    • nausea
  • Rare adverse effects
    • VITT
      • The combination of thrombosis and thrombocytopenia, in some cases accompanied by bleeding, has been reported post-market following vaccination with Vaxzevria™ (AstraZeneca). This adverse event is being referred to as Vaccine-induced Immune Thrombotic Thrombocytopenia (VITT).
      • Health Canada has released a safety alert; the product monographs now include this information in the Warnings and Precautions section.
      • Health Canada is soliciting further data from AstraZeneca, will continue to monitor and will take further action if necessary. 
    • Capillary leak syndrome
      • Very rare cases of capillary leak syndrome (CLS) have been reported following immunization with Vaxzevria™ COVID-19 vaccine. Some affected patients had a previous diagnosis of CLS. CLS is a serious, potentially fatal condition characterized by acute episodes of limb edema, hypotension, hemoconcentration and hypoalbuminemia. Individuals with a history of CLS should not receive Vaxzevria™.
    • Guillain-Barré Syndrome
      • Very rare events of demyelinating disorders, such as Guillain-Barré Syndrome (GBS), have been reported following vaccination with Vaxzevria™ during post-authorization use.

Drug Interactions

  • There are no known drug interactions. 

References:

  • Age
    • Vaxzevria™ COVID-19 Vaccine (AstraZeneca) is approved for use in persons 18 years of age and older. 

  • History of anaphylaxis following previous dose of the vaccine.

  • Reported hypersensitivity to one of the ingredients. See product monographs for ingredients. (Note: ingredients are the same in the two vaccines)
  • Individuals with a history of the following conditions should not receive this vaccine:
    • heparin-induced thrombocytopenia (HIT)
    • thrombosis associated with lupus anticoagulant (thrombotic antiphospholipid syndrome)
    • venous or arterial thrombosis with thrombocytopenia following viral vector COVID-19 vaccine
    • capillary leak syndrome

  • It is recommended individuals with a history of cerebral venous sinus thrombosis (CVST) with thrombocytopenia only receive this vaccine if benefit outweighs risk; mRNA COVID-19 vaccine is preferred.

  • Pregnancy
    • As of May 21, 2021, Vaxzevria™ is not to be routinely offered to pregnant individuals and instead these individuals should receive mRNA vaccines (i.e. Comirnaty™ [Pfizer], SPIKEVAX™ [Moderna]). 
      • Vaxzevria™ can be offered if:
        • allergy to any of the mRNA vaccine components, or
        • mRNA vaccine is not readily available
      • The reason for this recommendation is concerns about increased complexity in medical care if Vaccine-induced Immune Thrombotic Thrombocytopenia (VITT) were to occur following a viral vector vaccine.
    • Receipt of Vaxzevria™ during pregnancy is not a reason to terminate pregnancy.

  • Currently feeling unwell with symptoms that could be COVID-19.
    • to avoid confusion if symptoms arise/worsen as they could be adverse effects of the vaccine or because of the underlying infection
    • to prevent potential transmission to others who are at the vaccine clinic/site (clients should be following public health quarantine recommendations)

  • Serious adverse or allergic reaction to previous dose of COVID-19 vaccine unless determined safe by an allergist or other healthcare provider.

  • Breastfeeding/Immunocompromised/Autoimmune Conditions
    • These populations were excluded from the initial vaccine trials such that we had no data on safety and efficacy of the vaccines in these populations when vaccination started and decisions were based on risk-benefit assessments.
    • 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 Vaxzevria™ with mRNA vaccine.  
      • Regarding special populations, most of the data have come from mRNA vaccines.
      • However, Vaxzevria™ should be used if there are any contraindications to mRNA vaccine or if mRNA vaccine is not accessible.
    • See information in similarly titled tabs for the Comirnaty™ (Pfizer) and SPIKEVAX™ (Moderna) vaccines

References:

Current Infection

  • Clients with current infection should not present for vaccination to prevent transmission to others at the vaccination clinic/site and should follow public health quarantine recommendations.

Past Infection

  • If acute symptoms have resolved and all quarantine orders have been followed, the individual can be vaccinated.
    • Trial included <10% participants with previous COVID-19 infection proven by serology.

Reference: 

  • Previous direction had been to separate COVID-19 vaccine from all other vaccines based on limited safety, reactogenicity and immunogenicity evidence.
  • As of September 2, 2021, the Ministry of Health is authorizing COVID-19 vaccine to be administered concomitantly with other vaccines; no intervals are required before or after COVID-19 vaccine administration and another vaccine.
    • The Ministry of Health closely monitored simultaneous administration of COVID-19 and other vaccines as implemented in other jurisdictions over the past few months. No additional safety risks or adverse events following immunization have been identified by simultaneous administration of these vaccines.
    • This directive ensures that individuals have the opportunity to be immunized against COVID-19 when they are eligible to receive other vaccines such as influenza and school-aged vaccines.
    • Separate injection sites should be used when administering > 1 vaccine
      • Preferably use two different limbs but if need to inject >1 vaccine into the same limb, separate the two injection sites by at least 2.5 cm (1 inch).
    • Note that NACI continues to recommend separating COVID-19 vaccine from other vaccines and continues to monitor the evidence.
    • Minimum intervals between two COVID-19 vaccine doses are still required.
References: