WEST NILE VIRUS VACCINE
Live Flavivirus Chimera
DESCRIPTION:
PreveNile™ contains a lyophilized Yellow Fever West Nile (YF-WN) chimera virus vaccine. The human vaccine yellow fever virus, YF-17D, was used as the backbone. The YF-17D strain is a highly effective, well-tolerated live, attenuated vaccine that has been used for over 60 years to immunize approximately 400 million people1. The YF-17D virus was modified using molecular technology to form a YF-WN chimera virus that expresses the PreMembrane and Envelope proteins of WNV. Following injection, limited replication of the YF-WN chimera virus allows expression of these proteins that stimulate a protective immune response in the horse.
INDICATIONS:
For the vaccination of healthy horses to prevent viremia and as an aid in the prevention of disease and encephalitis caused by West Nile virus infection.
SAFETY DATA:
Studies have shown that the YF-WN chimera virus in PreveNile™ has limited to no replication in cells of mosquitoes or in the mosquito vectors of West Nile Virus or Yellow Fever Virus2. Studies of the YF-WN chimera virus in non-target animal species also show a lack of pathogenicity3. Safety studies have demonstrated that the vaccine virus is stable and does not revert to virulence, does not disseminate into the tissues of vaccinated horses, and is not shed by vaccinated horses following administrations. An overdose study, 10X the standard vaccine dose was administered to horses, no clinical signs were seen in any horses, nor was vaccine virus recovered from the plasma, nasal, oral, and rectal swabs or from tissues from these vaccinated horses. Transmission of vaccine virus to sentinel horses kept in contact with these vaccinated horses did not occur. In a large field safety study of 919 horses, PreveNile™ was demonstrated to be >99% reaction-free when administered to horses of various ages, breeds, and sex. Of the 919 horses vaccinated, 229 were 4 months of age or younger, and 302 were pregnant mares, including 17 mares in the first trimester of gestation, 11 mares in the second trimester of gestation and 274 mares in the third trimester of gestation. No post vaccinal adverse events were observed in any of the foals or mares. Studies to continue to evaluate safety in these mares through foaling are ongoing. The results of this study show the vaccine to be safe when used to vaccinate horses 4 months of age or older by the intramuscular route.
EFFICACY, ONSET OF IMMUNITY, AND DURATION OF IMMUNITY DATA:
For complete efficacy data, see the PreveNile™ package insert.
ADMINISTRATION AND DOSAGE:
Aseptically reconstitute the desiccated vaccine with the sterile diluent provided and administer 1 mL by the intramuscular route. Initial vaccination of healthy horses may be given as early as 5 months-of-age. For primary vaccination, administer a single dose only. Re-vaccinate annually with a single dose. For horses previously vaccinated against West Nile, administer a single dose only.
SUPPLIED:
Code: 034955 10 vials (1 dose each) of lyophilized vaccine, 10 vials (1 mL) of sterile diluent. Code: 042149 2 vials (5 doses each) of lyophilized vaccine, 2 vials (5 mL) of sterile diluent. U. S. Patent Nos: 6,878,372 and 6,962,708
REFERENCES:
1 Monath TP. Yellow fever: an update. Lancet. 2001:1:11-20.
2 Johnson B.W. et al. Growth characteristics of the veterinary vaccine candidate ChimeriVax™ - West Nile (WN) virus in Aedes and Culex mosquitoes. Medical and Veterinary Entomology. 2003:17:235-243.
3 Monath TP. et al. West Nile Virus Vaccine. Current Drug Targets – Infectious Disorders. 2001:1:37-50.
FOR USE IN ANIMALS ONLY
