Influvac

Package leaflet: Information for the user

Influvac, suspension for injection in pre-filled syringe
Influenza vaccine (surface antigen), inactivated
Season 2025/2026
Please read all of this leaflet carefully before the vaccine is administered to an adult or child, as it contains important information for the patient.

• Keep this leaflet, as you may need to read it again.
• If you have any further questions, please ask your doctor, pharmacist, or nurse.
• This vaccine has been prescribed for a specific adult or child. Do not pass it on to others.
• If any adverse reactions occur in the adult or child, including any adverse reactions not listed in this leaflet, inform your doctor, pharmacist, or nurse. See section 4.

Leaflet contents

1. What Influvac is and what it is used for
2. Important information before vaccination with Influvac in adults or children
3. How to use Influvac
4. Possible side effects
5. How to store Influvac
6. Contents of the pack and other information

1. What Influvac is and what it is used for

Influvac is a vaccine for adults and children from 6 months of age. This vaccine helps protect adults or children against influenza (flu). Use of the Influvac vaccine should follow official recommendations.
After vaccination with Influvac, the body's immune system (the body's natural defence system) produces its own protection (antibodies) against the disease. None of the components of the vaccine can cause influenza.
Influenza is a disease that can spread rapidly. It is caused by various strains of virus, which may change each year. For this reason, annual vaccination of adults or children may be necessary. The highest risk of influenza occurs during the colder months between October and March. If an adult or child has not been vaccinated in the autumn, vaccination is still recommended up to spring, as there remains a risk of contracting influenza during this time. Your doctor will determine the best time for vaccination.
Influvac protects adults and children against the three virus strains contained in the vaccine approximately 2–3 weeks after vaccination.
The incubation period of influenza in the body is several days; therefore, if an adult or child has been exposed to the virus shortly before or immediately after vaccination, there remains a possibility of developing influenza.
The vaccine does not protect adults or children against the common cold, even though some of its symptoms may resemble those of influenza.

2. Important information before administering the Influvac vaccine to an adult or child

To ensure that the Influvac vaccine is suitable for the patient, inform the doctor, pharmacist, or nurse if any of the following apply to the adult or child who is to receive the vaccine.
If in any doubt, please ask the doctor, pharmacist, or nurse for advice.

When not to use Influvac vaccine

• if the adult or child has a hypersensitivity (allergy) to:
  • the active substances or
  • any of the other ingredients of the Influvac vaccine (see section 6) or
  • any of the components that may be present in very small amounts, such as chicken eggs (chicken egg ovalbumin, chicken proteins), formaldehyde, trimethylcetylammonium bromide, polysorbate 80, or gentamicin (an antibiotic used to treat bacterial infections)

Warnings and precautions

Before administering the Influvac vaccine, inform the doctor if the adult or child has:

• weakened immune response (due to immunodeficiency or use of medications affecting the immune system)
• bleeding disorders or tendency to bruise easily

The doctor will decide whether the adult or child can be vaccinated.
If the adult or child has a disease with high fever or an acute infection, vaccination should be postponed until recovery.
Fainting, feeling faint or weak, or other stress-related reactions may occur before or after any injection. If the patient has previously experienced such a reaction after vaccination, they should inform the doctor or nurse.
Inform the doctor if blood tests are planned for the adult or child within a few days after influenza vaccination. In some patients, false positive blood test results have been observed shortly after influenza vaccination.
As with any vaccine, Influvac may not fully protect all vaccinated individuals.

Influvac and other medicines

• Inform the doctor, pharmacist, or nurse about all vaccines or medicines currently used or recently used by the adult or child, as well as any medicines the patient plans to take, including those available without a prescription.
• Influvac may be administered simultaneously with other vaccines, but each vaccine should be given in a different limb. Concurrent administration of vaccines may increase the frequency of adverse reactions.
• Immune response may be reduced when administered concurrently with medications that suppress the immune response, such as corticosteroids, cytotoxic drugs, or radiotherapy.

Pregnancy and breastfeeding

If the patient is pregnant or breastfeeding, suspects she may be pregnant, or plans to become pregnant, she should consult her doctor before receiving this vaccine.
Influenza vaccines may be used at any stage of pregnancy. More safety data are available for the second and third trimesters of pregnancy compared to the first trimester; however, worldwide data on influenza vaccination during pregnancy do not indicate any harmful effects on the pregnancy or the fetus.
Influvac may be used during breastfeeding.
The doctor, pharmacist, or nurse will decide whether Influvac vaccination is appropriate for a pregnant woman. Before using any medicine, consult a doctor, pharmacist, or nurse.

Driving and operating machinery

Influvac has no or negligible effect on the ability to drive or operate machinery.

Influvac contains sodium and potassium

The vaccine contains less than 1 mmol of sodium (23 mg) per dose, meaning it is considered "sodium-free".
The vaccine contains less than 1 mmol of potassium (39 mg) per dose, meaning it is considered "potassium-free".

3. How to use Influvac

Dosage
Adults should receive one dose of 0.5 ml.
Use in children and adolescents
Children from 6 months of age up to the day before their 18th birthday should receive one dose of 0.5 ml.
Children below 9 years of age who have not previously been vaccinated or have not been fully vaccinated
with seasonal influenza vaccine: a second dose of 0.5 ml should be administered at an interval of
at least 4 weeks.
Children below 6 months of age: safety and efficacy of Influvac vaccine have not been established.
Method and route of administration
The vaccine should be administered by a doctor or nurse intramuscularly or deeply subcutaneously.
If you have any questions concerning the use of this vaccine, consult your doctor, pharmacist, or
nurse.

4. Possible adverse reactions

Like all medicines, Influvac may cause adverse reactions, although not everyone experiences them.
If any of the following adverse reactions occur in an adult or child,
you should contact a doctor immediately – immediate medical intervention may be required:

Severe allergic reactions (frequency unknown, occurred sporadically during use of
the Influvac vaccine)

• in rare cases potentially requiring immediate medical assistance, manifesting as circulatory failure affecting adequate blood flow to various organs (shock)
• in very rare cases, swelling, most pronounced in the head and neck area, involving the face, lips, tongue, throat or other body parts, which may cause difficulty in swallowing or breathing (angioedema).

During clinical trials with the Influvac product and/or the quadrivalent Influvac Tetra vaccine,
the following adverse reactions were observed. Their frequency of occurrence was defined as:

• very common (may occur in more than 1 in 10 people);
• common (may occur in up to 1 in 10 people);
• uncommon (may occur in up to 1 in 100 people);
• frequency not known (adverse reactions from post-marketing experience; cannot be estimated based on available data)

In all age groups, the majority of the above-mentioned adverse reactions usually occurred within the first 3 days after vaccination and spontaneously resolved within 1 to 3 days from onset. Generally, these were adverse reactions of mild intensity.
Reporting of adverse reactions
If any adverse reactions occur, including any adverse reactions not listed in this leaflet, patients should inform their doctor, pharmacist, or nurse. Adverse reactions can be reported directly to the Department of Monitoring Adverse Drug Reactions at the Office for Registration of Medicinal Products, Medical Devices and Biocidal Products:
Al. Jerozolimskie 181C
02-222 Warsaw
Phone: +48 22 49 21 301
Fax: +48 22 49 21 309
Website: https://smz.ezdrowie.gov.pl
Adverse reactions can also be reported to the marketing authorization holder.
Reporting adverse reactions helps to provide more information on the safety of the medicinal product.

5. How to store Influvac

Keep the medicine out of the sight and reach of children.
Do not use this medicine after the expiry date stated on the carton and on the syringe after EXP. The expiry date refers to the last day of the stated month. The batch number is indicated on the carton and on the syringe after Lot.
Store in a refrigerator (2°C - 8°C). Do not freeze.
Keep the pre-filled syringe in the outer packaging to protect from light.
Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. This will help protect the environment.

6. Contents of the pack and other information

What Influvac contains
The active substances are:
Surface antigens of influenza virus (haemagglutinin and neuraminidase) corresponding to the
following strains*:
A/Victoria/4897/2022 (H1N1)pdm09-like strain (A/Victoria/4897/2022, IVR-238)
15 micrograms HA**
A/Croatia/10136RV/2023 (H3N2)-like strain (A/Croatia/10136RV/2023, X-425A)
15 micrograms HA**
B/Austria/1359417/2021-like strain (B/Austria/1359417/2021, BVR-26)
15 micrograms HA**
per 0.5 ml dose
* propagated in embryonated chicken eggs from healthy flocks
** haemagglutinin
This vaccine is in accordance with the recommendations of the World Health Organization (WHO)
(for the northern hemisphere) and EU recommendations for the 2025/2026 season.
Other components of the vaccine are: potassium chloride, potassium dihydrogen phosphate,
disodium phosphate dihydrate, sodium chloride, calcium chloride dihydrate, magnesium chloride
hexahydrate, water for injections.

What Influvac looks like and contents of the pack
The Influvac vaccine contains 0.5 ml of a colourless, clear suspension for injection in a glass
prefilled syringe with a plunger stopper (bromobutyl rubber) with or without needle. Each prefilled
syringe must be used only once.
Pack sizes of 1 or 10 prefilled syringes.
Not all pack sizes may be marketed.

Marketing Authorisation Holder
Viatris Healthcare Limited
Damastown Industrial Park
Mulhuddart
Dublin 15
DUBLIN
Ireland

Manufacturer
Abbott Biologicals B.V.
Veerweg 12
8121 AA Olst, The Netherlands

For further information, contact the Marketing Authorisation Holder's representative:
Viatris Healthcare Sp. z o.o.
tel. 22 546 64 00

This medicinal product is authorised in the Member States of the European Economic Area and in the United Kingdom (Northern Ireland) under the following names:

The following information is intended solely for medical or healthcare personnel:

As with all injectable vaccines, appropriate facilities for immediate treatment and proper medical care must be available in case of anaphylactic reactions following vaccination.

The vaccine should reach room temperature. Shake well before use.
Inspect visually prior to administration.
Do not use the vaccine if it has changed color or if particulate matter is present in the suspension.
Do not mix with other medicinal products in the same syringe.
The vaccine must not be administered directly into blood vessels.
Preferred sites for intramuscular injection are the anterolateral aspect of the thigh (or the deltoid muscle if muscle mass is adequate) in children from 6 months up to 35 months of age, or the deltoid muscle in children from 36 months of age and in adults.

Identifiability
To improve the traceability of biological medicinal products, the name and batch number of the administered product should be clearly documented.

See also section 3: How to use Influvac.