Virbagen Omega

Virbagen Omega is a lyophilisate (freeze-dried pellet) and solvent that are made into a suspension for injection. Virbagen Omega contains the active substance recombinant omega interferon of feline origin (from cats) at 5 MU/vial or 10 MU/vial. It is used for dogs and cats.

Virbagen Omega is used to reduce mortality and clinical signs of parvovirosis (a highly contagious viral infection of dogs) in dogs from one month of age.

Virbagen Omega is also used to treat cats infected with feline leukaemia virus (FeLV) or feline immunodeficiency virus (FIV), in non-terminal cats from the age of nine weeks.

Dogs: The suspension should be injected intravenously (into a vein) once daily for three consecutive days. The dose is 2.5 MU/kg bodyweight.

Cats: The suspension should be injected subcutaneously (under the skin) once daily for five consecutive days. The dose is 1 MU/kg bodyweight. Two further five-day treatments must be carried out at 14 days and at 60 days after the first five-day course.

Virbagen Omega contains the active substance recombinant omega interferon. Interferons are a family of naturally occurring proteins that are produced in response to viral infections. Virbagen Omega works by stimulating the immune system to attack the virus. The active substance of Virbagen Omega, omega interferon, is produced by a method known as ‘recombinant technology’. The omega interferon is made by a cell that has received a gene (DNA), which makes it able to produce omega interferon. The replacement omega interferon acts in the same way as naturally produced omega interferon.

Virbagen Omega has been studied in dogs (males and females) of at least five weeks old that were infected with parvovirosis. Virbagen Omega 2.5 MU/kg was given intravenously for 3 days. The main measure of effectiveness was the mortality rate compared with dogs that had not been treated. Virbagen Omega has also been studied in the treatment of anaemic or non-anaemic cats infected with FeLV or FIV from the age of nine weeks. The main measure of effectiveness was the mortality rate compared with cats that had not been treated and clinical signs after treatment.

The mortality rate for dogs treated with Virbagen Omega was 4.4-6.4 times lower than that of the untreated animals.

In the treatment of cats with FeLV, there was a reduction of clinical signs over four months and a reduction in the mortality rate. In anaemic cats, the mortality rate in cats infected by FeLV (about 60%) was reduced by about 30%. In non-anaemic cats, the mortality rate (50 %) was reduced by 20%. In cats infected by FIV, the mortality rate was low (5%) and was not changed by the treatment. In the population of cats (whether they were FeLV-positive, FIV-positive or co-infected by both viruses) there was a reduction of clinical signs over time, improving the quality of life of the cats.

The injection of Virbagen Omega may cause the following temporary symptoms in dogs and cats:

• hyperthermia (increased temperature, three to six hours after injection);
• transitory vomiting;
• soft faeces to mild diarrhoea, in cats only;
• fatigue during the treatment, in cats only.

There may be a slight decrease in white blood cells, platelets and red blood cells, and a rise in the concentration of alanine aminotransferase (a liver enzyme). These symptoms return to normal in the week after the last injection.

In case of accidental self-injection, seek medical advice immediately and show the package leaflet or the label to the doctor.

The Committee for Medicinal Products for Veterinary Use (CVMP) agreed that the benefits of Virbagen Omega are greater than any risks to reduce mortality and clinical signs of parvovirosis in dogs from one month of age, and to treat cats infected with FeLV (feline leukaemia virus) or FIV in non-terminal cats from the age of nine weeks. They recommended that Virbagen Omega should be given a marketing authorisation. The benefit-risk balance may be found in module 6 of this EPAR.

The European Commission granted a marketing authorisation valid throughout the European Union for Virbagen Omega to Virbac SA on 6 November 2001. Information on the prescription status of this product may be found on the labelling.