EMA backs first-of-its-kind multivalent feline vaccine incorporating self-amplifying RNA technology

European medicines regulatory agency has endorsed a five-pathogen feline vaccine that combines live attenuated strains with self-amplifying RNA technology, with data showing rapid onset of immunity and reduced disease burden

The European Medicines Agency (EMA) has recommended the grant of a marketing authorisation for Nobivac NXT HCPChFeLV, a multivalent vaccine intended to protect cats against a range of common infectious diseases. The decision marks a notable step in veterinary immunisation, as the product is the first in the European Union to include self-amplifying RNA as an active component.

The vaccine has targeted five clinically significant feline pathogens: feline herpesvirus type 1, feline calicivirus, feline panleucopenia virus, feline leukaemia virus and the bacterium Chlamydia felis. These agents represent a substantial burden in companion animal medicine, with implications for respiratory disease, gastrointestinal illness, immunosuppression and oncogenesis.

Nobivac NXT HCPChFeLV has combined live attenuated strains of feline herpesvirus type 1 (G2620A), feline calicivirus (F9), feline panleucopenia virus (MW-1) and Chlamydia felis (Baker). These weakened organisms have stimulated an adaptive immune response, enabling the host to recognise and respond rapidly to subsequent exposure. For feline leukaemia virus, the formulation has employed a distinct platform: self-amplifying RNA delivered via a replication-deficient viral replicon particle. This system has enabled host cells to produce a viral protein antigen in situ, thereby priming immune defences against future infection.

To establish safety and efficacy, the Committee for Veterinary Medicinal Products of the EMA has assessed evidence from 15 controlled laboratory studies and one field investigation involving 142 cats under typical conditions of care. The data have demonstrated that the vaccine induces protective immune responses against all five pathogens, with onset of immunity observed approximately one week after administration. The duration of protection has extended to three years for feline panleucopenia virus and one year for the remaining pathogens.

Clinical outcomes have indicated a consistent reduction in disease burden. Investigators have reported decreases in mortality, clinical signs and pathogen shedding across multiple infections. In particular, the vaccine has reduced mortality and viral dissemination associated with feline herpesvirus type 1, mitigated clinical manifestations of feline calicivirus and prevented mortality and haematological complications such as leucopenia in feline panleucopenia virus infection. Additional benefits have included reduced clinical signs and bacterial shedding in Chlamydia felis infection, alongside diminished viraemia and symptom severity in feline leukaemia virus infection.

The safety profile has remained consistent with established expectations for veterinary vaccines. Adverse events have occurred in between 1 and 10 out of 100 treated animals and have typically involved transient swelling at the injection site or a mild elevation in body temperature, both resolving within approximately 24 hours. The product has also been considered safe for individuals who administer the vaccine and for the environment when used in accordance with the summary of product characteristics.

Manufacturing controls and batch testing have met regulatory standards, with evidence to support consistent product quality. On this basis, the Committee for Veterinary Medicinal Products has concluded that the benefit–risk balance is favourable.

The recommendation has now moved to the European Commission, which will consider the opinion and is expected to issue a legally binding decision applicable across all European Union member states.

Read more about the vaccine here