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POM-V Prescription Required Companion Animal

Virbagen Omega 10 MU Lyophilisate and Solvent for Suspension for Injection for Dogs and Cats

Active ingredients: Interferon omega, recombinant, feline

Form

Injection

Species

Cats Dogs

Manufacturer

Virbac

VMD MA No.

05653/5021

What it's used for

Cats: Treatment of cats infected with FeLV (feline leukemia virus) and/or FIV (feline immunodeficiency virus), in non-terminal clinical stages, from the ag...

Full indications, dosage and side effects ↓
View official SPC (PDF)

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Clinical information

Virbagen Omega 10 MU Lyophilisate and Solvent for Suspension for Injection for Dogs and Cats — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 27 Mar 2026.

Cats:
Treatment of cats infected with FeLV (feline leukemia virus) and/or FIV (feline
immunodeficiency virus), in non-terminal clinical stages, from the age of 9 weeks. In a field
study conducted, it was observed that there was:
- a reduction of clinical signs during the symptomatic phase (4 months)
- a reduction of mortality:
•
reduced by approximately 30% following treatment with interferon.
•
by 20% following treatment with interferon. In cats infected by FIV, mortality was
low (5%) and was not influenced by the treatment.
Dogs:
The reconstituted veterinary medicinal product should be injected intravenously once daily
for 3 consecutive days.
The dose is 2.5 MU/kg bodyweight.
Cats:
The reconstituted veterinary medicinal product should be injected subcutaneously once
daily for 5 consecutive days. The dose is 1 MU/kg bodyweight. Three separate 5-day
treatments must be performed at day 0, day 14 and day 60.
The veterinary medicinal product should be used with the accompanying solvent only.
Dogs: Vaccination during and after treatment with this veterinary medicinal product is
contraindicated, until the dog appears to have recovered.
Cats: as vaccination is contraindicated in the symptomatic phase of FeLV/FIV infections,
the effect of this veterinary medicinal product on cat vaccination has not been evaluated.
Dogs:
Very common
(>1 animal / 10 animals treated):
Decreased white blood cells
, Decreased platelet
count
, Decreased red blood cell count
, Elevated
alanine aminotransferase (ALT)
Common
(1 to 10 animals / 100 animals
treated):
Hyperthermia
2,3
Lethargy
1
Slight, Return to normal in the week following the last injection.
Slight and Transient.
3-6 hours after injection.
Cats:
Very common
(>1 animal / 10 animals treated):
Decreased white blood cells
, Decreased platelet
count
, Decreased red blood cell count
, Elevated
alanine aminotransferase (ALT)
Common
(1 to 10 animals / 100 animals
treated):
Hyperthermia
2,3
Lethargy
Digestive tract disorders (e.g. Diarrhoea, Vomiting)
1
Slight, Return to normal in the week following the last injection.
Slight and Transient.
3-6 hours after injection.
Reporting adverse events is important. It allows continuous safety monitoring of a
veterinary medicinal product. Reports should be sent, preferably via a veterinarian, to
either the marketing authorisation holder or its local representative or the national
competent authority via the national reporting system. See the package leaflet for
respective contact details.
No information on the induction of long-term adverse reactions is available in dog and cat,
especially for autoimmune disorders. Such adverse effects have been described after
multiple and long-term administration of type I interferon in man. The possibility of
occurrence of autoimmune disorders in treated animals cannot therefore be ruled out and
has to be balanced with the risk associated with FeLV/FIV infections.
Efficacy of the veterinary medicinal product on cats with a tumorous form of the infection
by FeLV, or cats infected by FeLV or coinfected by FIV in terminal stages was not tested.
In the case of intravenous administration in cats, increased adverse reactions may be
seen, e.g. hyperthermia, soft faeces, anorexia, decreased drinking or collapse.

Special precautions for safe use in the target species:
Dogs and cats: it was shown that strict compliance with the recommended posology is
compulsory to achieve clinical benefit.
Cats: In case of repeated treatments of chronic diseases associated with hepatic, cardiac
and renal failure, the corresponding disease has to be monitored prior to administration of
this veterinary medicinal product.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
In case of accidental self-injection, seek medical advice immediately and show the
package leaflet or the label to the physician.
Special precautions for the protection of the environment:
Not applicable.
The use of supplementary supportive treatments improves prognosis. No interaction has
been observed during the treatment with this veterinary medicinal product together with
antibiotics, solution for rehydration, vitamins and non steroidal anti-inflammatory agents.
However, as specific information on possible interactions of interferon with other products
are missing, supplementary supportive treatments should be used cautiously and after a
thorough risk/benefit analysis.
No information is available on the safety and efficacy of this veterinary medicinal product
when used with any other vaccine. For dogs, it is recommended that no vaccines should
be administered until the animal appears to have recovered. Cat vaccination during and
after treatment this veterinary medicinal product is contraindicated as both FeLV and FIV
infections are known to be immunosuppressive.
Store and transport refrigerated (2 °C – 8 °C).
Do not freeze.
Store in the original package.
Not applicable.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.

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