Medical Advisory: Moderna XBB and Arexvy

Issued by: Dr. Azim Kasmani, MD MSc FRCPC, Medical Officer of Health

Date: September 29, 2023

Vaccine Rollout for COVID-19 Vaccine 

• Niagara Region Public Health (NRPH) will have Moderna XBB containing COVID-19 vaccine in our clinics starting Oct. 3 for individuals at high-risk for influenza and / or COVID-19 related complications or hospitalization. Appointment availability will be limited initially.
  • NRPH will also be supporting vaccination efforts to residents in Long Term Care Homes and Retirement Homes
• In the weeks that follow, the Ministry of Health has indicated that COVID-19 vaccine will continue to be distributed as soon as more vaccine becomes available for primary care providers and pharmacies. The COVID-19 vaccine product and timelines for distribution will be shared when known.

Moderna XBB Recommendations

The new XBB vaccine formulation generates a strong immune response to the most recent descendants of the XBB variants. The Ministry of Health has issued new recommendations for staying up to date with COVID-19 vaccination using XBB:

• Individuals in the authorized age group (i.e. six months and older) who have been previously vaccinated against COVID-19 are recommended to receive a dose of XBB containing COVID-19 vaccine if it has been six months from the previous COVID-19 vaccine dose or known SARS-CoV-2 infection
• Individuals who have NOT been previously vaccinated may use the XBB to initiate the series

Health Care Provider Action for Moderna XBB

Counsel all patients six months and older to receive an XBB dose as soon as it becomes available to them. Additional information for specific groups below:

• Previously unvaccinated patients who are 12 to 29 years old. Counsel these patients that National Advisory Committee on Immunization (NACI) previously issued a preferential recommendation for this age group to use Pfizer for a primary series. Health care providers offering Moderna XBB should inform their patients that the NACI recommendations related to myocarditis and /or pericarditis are still pending.
• Immunocompromised patients
  • Who have been previously vaccinated are strongly recommended to receive a XBB containing COVID-19 vaccine this fall
  • Guidance on whether an additional dose is recommended for these populations is still pending
• Patients six months of age and older vaccinated with one or more non-Health Canada approved vaccine(s) are recommended to receive a dose of XBB COVID-19 vaccine

Vaccine Rollout for Arexvy for RSV

• NRPH will be supporting Respiratory Syncytial Virus (RSV) vaccination efforts to residents in Long Term Care Homes and select Retirement Home residents

• There is no other information on publicly funded RSV vaccine distribution at this time

Co-Administration Information for Arexvy and Other Vaccines 

• Arexvy vaccine for RSV should not be co-administered with other vaccinations, including COVID-19 and influenza vaccines. It is recommended to wait at least two weeks before or after administration of the RSV vaccine. These suggested waiting periods are precautionary but may help prevent erroneous attribution of an AEFI to one particular vaccine or the other.
  • If there are extenuating circumstances, co-administration of Arexvy with other vaccines, including COVID-19 and influenza vaccines, is permitted

More Information

• Call the Vaccine Preventable Disease program at 905-688-8248 or 1-888-505-6074 ext. 7396
• Moderna XBB
  • Join the COVID-19 Vaccine Administration Program for Physicians and Primary Care
  • Ministry of Health COVID-19 Vaccine Guidance (see page 7 for high-risk groups)
• Arexvy
  • NACI is reviewing the use of Arexvy. Recommendations and a chapter update to the Canadian Immunization Guide are pending.
  • Regulatory Decision Summary for Arexvy
• Pfizer XBB
  • Health Canada approved Pfizer XBB on Sept. 28. Further information is pending. For now, see Regulatory Decision Summary for Comirnaty Omicron XBB.1.5