Public Summary SwissPAR – Efluelda®

Public Summary SwissPAR dated 30.05.2022

Efluelda® (active substance: Influenza viruses (inactivated, split) of the following strains: A (H1N1), A (H3N2), B (Yamagata) and B (Victoria))

First authorisation in Switzerland: 21 July 2021

Medicinal product (vaccine) for the prevention of influenza (flu)

About the medicinal product

The medicinal product Efluelda contains the inactivated and split influenza viruses of the strains A (H1N1), A (H3N2), B (Yamagata) and B (Victoria) as the active substance. It is a suspension for injection in a pre-filled syringe.

Efluelda is a vaccine used for the prevention of influenza (flu) caused by the two influenza A virus types and the two influenza B virus types included in the vaccine.
Efluelda is used in adults 65 years of age and older.

Efluelda is a quadrivalent high-dose vaccine, which means that the vaccine contains four times the amount of antigen[1] compared to most influenza vaccines.

Flu is a disease of the respiratory tract caused by influenza viruses and that infects the nose, throat and lungs. Small children, the elderly and especially vulnerable individuals are at increased risk of suffering from a serious complication of flu.

Each year, seasonal flu leads to more than 250,000 visits to the doctor in Switzerland. As a result of possible complications, flu is responsible for thousands of hospital stays and several hundred deaths a year.

Flu vaccination is the most important public healthcare measure for reducing the annual burden associated with flu epidemics. The most commonly used flu vaccines are inactivated influenza viruses.

The WHO recommends the composition of the seasonal flu vaccine for the northern hemisphere in the first quarter of a given calendar year based on the circulating viruses.

[1] Antigen: A substance or structure that is recognised by the body as ‘foreign’, thereby triggering an immune reaction in the body.

Mode of action

The Efluelda vaccine causes the immune system (the body's natural defences) to produce antibodies and blood cells that work against the virus strains administered, thereby affording protection against influenza.

For a more detailed explanation of the mode of action of vaccines, we recommend the Swissmedic videos on vaccines in general.


The Efluelda vaccine is injected into a muscle, preferably the shoulder muscle, by a correspondingly trained healthcare professional. One dose is administered.

Efluelda should be used in accordance with the official vaccination recommendations.


Two studies (QHD00013 and FIM12) were submitted with the authorisation documents.

Study QHD00013 investigated the safety and immunogenicity[2] of Efluelda compared to the trivalent high-dose flu vaccine (TIV-HD) in more than 2,000 healthy adults aged over 65. The study showed that Efluelda induced a level of immunogenicity in over-65-year-olds that was no weaker compared to TIV-HD.

Study FIM12 investigated the efficacy of TIV-HD. The study was conducted in healthy adults aged over 65 who received TIV-HD or a vaccine at a standard dosage (Fluzone). The efficacy was observed over two seasons in a total of more than 30,000 study participants. The efficacy of TIV-HD proved to be superior to that of the standard-dose vaccine.

In addition to the data from the two studies QHD00013 and FIM12 described above, data from the still ongoing study QHD00011 have also been reviewed by Swissmedic. These provided further information confirming the immunogenicity and safety of Efluelda.

[2] Immunogenicity: Immunogenicity is the ability of a substance (antigen) to trigger an immune reaction in the body.

Precautions, undesirable effects & risks

Efluelda must not be used in those who are hypersensitive to the active substance or any of the excipients.

Like all vaccines, Efluelda can also produce side effects, although not necessarily in everyone. The most common undesirable effects are pain at the injection site, myalgia (muscle pain), headache and malaise. Like all vaccines, an anaphylactic reaction (acute allergic reaction) can occur following the administration of Efluelda. Therefore, the doctor should monitor patients after the vaccination and, if necessary, initiate medical measures.

As with other vaccines, for those who are suffering from a moderate or severe acute illness with or without fever, vaccination with Efluelda should be postponed to a later date.

All precautions, risks and other possible undesirable effects are listed in the Information for healthcare professionals (see link at the end of this document).

Why the medicinal product has been authorised

Flu vaccination is the cornerstone of public healthcare in reducing the annual burden associated with flu epidemics. Vaccination against the flu is recommended particularly for especially vulnerable individuals who have a higher risk of experiencing complications or a serious case of influenza. The risk is highest in those aged over 65. The pivotal studies have demonstrated the efficacy of Efluelda and also provided data on safety.

Taking all the risks and precautions into account, and based on the available data, the benefits of Efluelda outweigh the risks.

Swissmedic has therefore authorised the vaccine Efluelda, containing the inactivated and split influenza viruses of the strains A(H1N1), A (H3N2), B (Yamagata) and B (Victoria) as the active substance, for Switzerland.

Further information on the medicinal product

Information for healthcare professionals:

Healthcare professionals can answer any further questions.


The date of revision of this text corresponds to that of the SwissPAR. New information concerning the authorised medicinal product in question will not be incorporated into the Public Summary SwissPAR.

Swissmedic monitors medicinal products authorised in Switzerland. Swissmedic initiates the necessary action in the event of newly discovered adverse drug reactions or other safety-relevant signals.

New findings that could impair the quality, efficacy or safety of this medicinal product are recorded and published by Swissmedic. If necessary, the medicinal product information is adapted.