Recombinant feline interferon omega

Recombinant feline interferon omega (RFeIFN-ω), sold under the brand name Virbagen Omega among others, is a recombinant version of a cat interferon alpha.^[1] It is used to treat a range of viral diseases in cats and dogs, including canine parvovirus, feline leukemia virus (FeLV), and feline immunodeficiency virus (FIV) in many countries. It is approved to be used by injection under the skin. RFeIFN-ω is produced in silkworm larvae using a baculovirus vector.^[2]

Recombinant feline interferon omega

Clinical data
Trade names	Virbagen Omega, Intercat, Virbac
ATCvet code	QL03AB90 (WHO)
Legal status
Legal status	Approved in JP, AU/NZ, MX, CN
Identifiers
CAS Number	1253735-49-7

Interferon alpha "omega-like"
Identifiers
Organism	Felis catus
Symbol	?
UniProt	P35849
Search for Structures Swiss-model Domains InterPro

Side effects include hyperthermia and decrease in white blood cell count. These effects tend to be mild and transient. It is a immunostimulant in the interferon family.^[3]

The feline interferon "omega" gene was first cloned in 1992.^[4] It was first produced in silkworms by Ueda and coworkers in 1993. The protein is around 60% identical to human alpha interferons, but the Ueda team deemed it an "omega-type" interferon due to some motifs.^[5] Phylogenic analysis in 2007 puts it as an alpha-type interferon.^[1]

Research

As the approved regimen is very costly, RFeIFN-ω has been experimentally used via other routes, including topical and oral protocols.^[2] RFeIFN-ω has also been used off-label to treat other viral infections. It has also been tried on cancer cell cultures.^[2]

RFeIFN-ω, delivered topically, is ineffective against feline upper respiratory tract disease caused by feline calicivirus.^[6]

Notes

References

1. Yang LM, Xue QH, Sun L, Zhu YP, Liu WJ (February 2007). "Cloning and characterization of a novel feline IFN-omega". Journal of Interferon & Cytokine Research. 27 (2): 119–27. doi:10.1089/jir.2006.0094. PMID 17316139.
2. Li SF, Zhao FR, Shao JJ, Xie YL, Chang HY, Zhang YG (November 2017). "Interferon-omega: Current status in clinical applications". International Immunopharmacology. 52: 253–260. doi:10.1016/j.intimp.2017.08.028. PMC 7106160. PMID 28957693.
3. EMEA (2004). "Scientific Discussion: Virbagen Omega, INN-interferon" (PDF). ema.europa.eu.
4. Nakamura N, Sudo T, Matsuda S, Yanai A (February 1992). "Molecular cloning of feline interferon cDNA by direct expression". Bioscience, Biotechnology, and Biochemistry. 56 (2): 211–4. doi:10.1271/bbb.56.211. PMID 1377975.; GenBank Accession number: E02521
5. Ueda Y, Sakurai T, Kasama K, Satoh Y, Atsumi K, Hanawa S, et al. (February 1993). "Pharmacokinetic properties of recombinant feline interferon and its stimulatory effect on 2',5'-oligoadenylate synthetase activity in the cat". The Journal of Veterinary Medical Science. 55 (1): 1–6. doi:10.1292/jvms.55.1. PMID 7681698.; GenBank Accession number: S62636
6. Ballin AC, Schulz B, Helps C, Sauter-Louis C, Mueller RS, Hartmann K (December 2014). "Limited efficacy of topical recombinant feline interferon-omega for treatment of cats with acute upper respiratory viral disease". Veterinary Journal. 202 (3): 466–70. doi:10.1016/j.tvjl.2014.09.030. PMID 25457261.