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COVID-19 treatment information for providers and prescribers

The Government of Ontario recently expanded eligibility for COVID-19 antiviral treatments to more high-risk individuals.

Paxlovid is an antiviral medication which targets the SARS-CoV-2 protease. It has been shown to be effective for prevention of hospitalization and death in symptomatic patients who are at higher risk of severe disease from COVID-19. 

To be considered for treatment with Paxlovid, patients must have tested positive for COVID-19 with a PCR or RAT, be experiencing symptoms of COVID-19 for ≤ five days and be at higher risk of developing severe disease because of underlying risk. 

The following FAQ includes more details about eligibility and treatment in Ottawa.

The following higher risk groups are eligible to be tested and assessed for antiviral treatments, such as Paxlovid, in Ontario:

  • Immunocompromised (have an immune system that is weakened by a health condition or medications)
  • 70 years of age and older
  • 60 year of age and older with less than three vaccine doses
  • 18 years of age or older with less than three vaccine doses and at least one risk condition:
    • Diabetes
    • Obesity
    • Heart disease
    • Hypertension
    • Congestive heart failure
    • Chronic lung disease (including cystic fibrosis)
    • Moderate or severe kidney disease
    • Intellectual or developmental disability
    • Cerebral palsy
    • Sickle cell disease
    • Moderate or severe liver disease
    • Pregnancy

Health care providers may also determine if antiviral treatment is appropriate for patients based on individual circumstances even if they do not belong to one of the groups listed.

In Canada, Paxlovid is not approved for routine use in children and youth less than 18 years of age. Treatment of medically fragile children and youth at the very highest risk of suffering severe complications may be considered by the medical specialists who manage their care needs.

It is important to remember that treatment for antivirals must be started within five days (depending on treatment) of when symptoms began.

Many patients who develop symptoms of COVID-19 will reach out to trusted health care providers to ask whether they are eligible for treatment. Health care providers have an important role in assessing these patients for eligibility and directing them into the appropriate pathway to receive treatment if they may be eligible.

The pathway below outlines steps for providers when potentially eligible patients ask about treatment:

  1. Prioritize

Prioritize assessment of patients who have symptoms of COVID-19 and may be at higher risk for severe disease within 24 hours of the patient seeking support

Direct patient to a clinical assessment centre or other local pathway as appropriate to receive an assessment, test, diagnosis, and disposition (including treatment with Paxlovid if appropriate)

  1. Assess

Assess patient to determine if treatment with Paxlovid is appropriate. Test patient or direct patient to get tested as appropriate

  1. Prescribe or Direct
    If the provider decides the patient should receive Paxlovid, they can:
  • Prescribe the medication directly, to be dispensed at a community pharmacy
  • Direct the patient to the TOH Clinical Assessment Centre if the patient is eligible for treatment with Remdesivir (patients with COVID-19 who are at higher risk of severe disease from COVID-19 and who cannot be treated with Paxlovid may be eligible for treatment with Remdesivir)
  1. Follow up
    Follow up with the patient as appropriate. Processes for follow-up within clinical assessment centres and local pathways will vary

For more detailed information about the patient pathway, please review Ontario Health’s guidance for health care providers.

There are three clinical assessment centres/care clinics across the Ottawa region where adults can get tested, assessed, and provided treatment or a prescription:

  • The Ottawa Hospital Clinical Assessment Centre – 1081 Carling Ave, Suite 601, Ottawa
  • Moodie COVID-19 Care and Testing Centre – 595 Moodie Drive, Ottawa
  • North Grenville COVID-19 Assessment Centre – 15 Campus Drive, Kemptville

An appointment for an in-person assessment at the above clinical assessment centres and care clinics must be booked in advance. Residents can visit to book an appointment.

If your patient is outside of Ottawa, use this locator tool to find the nearest clinical assessment centre by filtering by location type.

Paxlovid contains ritonavir, which acts as a “booster” by inhibiting metabolism of the active drug nirmatrelvir. This also has the effect of interfering with many other medications, which may have to be adjusted or held during treatment with Paxlovid.

It is recommended that providers review for drug-drug interactions before prescribing. Please visit the COVID-19 Science Table website to learn what prescribers and pharmacists need to know, and the COVID-19 drug interactions checker.  

All Paxlovid prescriptions can be filled at participating pharmacies, and do not require review by The Ottawa Hospital’s COVID-19 Therapeutics Clinic. Refer to the Ontario COVID-19 website for a list of participating pharmacies. 

Patients with COVID-19 who are at higher risk of severe disease from COVID-19 and who cannot be treated with Paxlovid may be eligible for treatment with Remdesivir. For patients in Ottawa, this therapy is only provided at the TOH Clinical Assessment Centre located at 1081 Carling Avenue, Suite 601.  

Remdesivir is an intravenous (IV) antiviral medicine to treat COVID-19, which has been demonstrated to prevent progression to severe disease in outpatients at higher risk of disease progression who are within seven days of symptom onset.  

Eligibility for Remdesivir is not equivalent to that for Paxlovid. Patients will be considered for Remdesivir if they are at higher risk of progression to severe disease as defined by the Ontario Science Table guideline, and cannot receive Paxlovid because of a definite contra-indication. Patients will have to attend at the infusion centre on three consecutive days for treatment. 

For patients who may meet criteria for use of Remdesivir and are able to attend the antiviral clinic, please submit a referral to the COVID-19 Therapeutics Clinic. The form is available for all physicians and can be sent to our clinic through fax at 613-739-6751. It is also available through the Ocean eReferral platform. If IV therapy is required and the patient is eligible, our team will reach out to the patient to coordinate treatment.

Key resources

Guidance for health care providers: Access to COVID-19 antiviral treatment (Paxlovid)
Information for primary care providers and other health care providers caring for patients in the community.

COVID-19 Science Advisory Table’s clinical guidelines
These guidelines identify populations who would benefit most from Paxlovid based on a threshold of 5% risk of hospitalization. They can be used by health care providers, along with the criteria above and clinical judgement, to inform decisions on when to prescribe.

Nirmatrelvir/Ritonavir (Paxlovid): What Prescribers and Pharmacists Need to Know
Key information to help prescribers determine whether Paxlovid is right for their patients.

Paxlovid product monograph
Full details on interactions and contraindications.
Ontario’s antiviral screener tool to help patients determine if they should be assessed for treatment.

Patient handout: Antiviral treatment
Information for patients to understand the benefits, who is eligible, and what to do if they get sick.

Ministry of Health website: COVID-19 antiviral treatment Information for the public, including who may be at higher risk and how to access treatment.

Information about Evusheld 

Evusheld is a combination of two monoclonal antibodies given intramuscular for the prevention of severe COVID-19 disease in people who are at higher risk. It has a half-life of six to nine months. The efficacy of Evusheld against currently circulating variants is known, but protection against future emerging variants cannot be guaranteed. 

Eligibility for Evusheld is determined by Ontario health using a tiered approach based on risk for severe disease outcome and predicted poor vaccine response. For the current eligibility criteria and details on the tiers please consult the Information about Evusheld (Tixagevimab and Cilgavimab): Reference for health care providers who may be prescribing or administering Evusheld  

To be eligible for treatment, patients must:  

Be at least 12 years old  

Weigh at least 40 kg  

Not have a current COVID-19 infection  

Not have a recent COVID-19 exposure  

Before receiving Evusheld, eligible individuals should be screened to ensure they are not currently symptomatic or known to be infected with COVID-19. Individuals should also be screened to ensure they have no recent high-risk exposure to a confirmed or probable case of COVID-19 during the close contact’s period of communicability. PCR, rapid antigen, and antibody testing are not required prior to receiving Evusheld. 

Currently there are no known contraindications to Evusheld apart from history of hypersensitivity to the drug or its components. Evusheld use may be associated with a small increased risk of cardiac events or VTE, particularly in patients who have unstable cardiac disease or who are already at higher risk of these events. Evusheld has also been associated with transient thrombocytopenia after administration, but an increased risk of bleeding was not observed in clinical trials in association with this thrombocytopenia.  

Evusheld is not licensed for use as a treatment for COVID-19 infection, it is only indicated for use in patients without active COVID-19 disease to prevent future infection. Patients should not be given Evusheld if they have symptoms of COVID-19 or a recent exposure within the previous 20 days. 

There is a limited supply of Evusheld available in Ontario. While access to Evusheld remains limited by supply, patient eligibility will be determined according to the relative risk of severe disease according to a framework created by Ontario Health, 

Patients who are eligible for Evusheld can be referred to the Evusheld Clinic at TOH directly via Epic, or by faxing a referral form.

Key resources 

Information about Evusheld (Tixagevimab and Cilgavimab): Reference for health care providers who may be prescribing or administering Evusheld  
Information for primary care providers and other health care providers caring for patients in the community. 

Memo – Access to Evusheld  
A memo to primary care providers and other health care providers about accessing Evusheld.  

Patient handout – Evusheld  
Information for patients to understand Evusheld, its benefits and eligibility.  

Last updated on: November 5th, 2023