Comparative Efficacy of Feline Leukemia Virus (FeLV) Inactivated Whole-Virus Vaccine and Canarypox Virus-Vectored Vaccine during Virulent FeLV Challenge and Immunosuppression

Patel, M.; Carritt, K.; Lane, J. G.; Jayappa, Huchappa; Ståhl, Marie; Bourgeois, Melissa

doi:10.1128/cvi.00034-15

Cited by 21 publications

(24 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another advantage is that FeLV vaccines released in U.S. in 1990–1991 were inactivated (i.e., killed) whole virus vaccines [ 25 , 26 ] which set a precedent of inactivated virus vaccine for future feline retroviral vaccines. In fact, the inactivated whole FeLV vaccine (Nobivac ® FeLV) was more effective than the recombinant canarypox virus vectored FeLV vaccine (Purevax ® FeLV) [ 27 ]. In addition, the long-term use of the inactivated whole FeLV vaccine demonstrated that this vaccine can be safely used in pet cats without any known incidence of FeLV infection from vaccine virus [ 27 , 28 ].…”

Section: Introductionmentioning

confidence: 99%

Lessons Learned in Developing a Commercial FIV Vaccine: The Immunity Required for an Effective HIV-1 Vaccine

Sahay

Yamamoto

2018

Viruses

View full text Add to dashboard Cite

The feline immunodeficiency virus (FIV) vaccine called Fel-O-Vax® FIV is the first commercial FIV vaccine released worldwide for the use in domestic cats against global FIV subtypes (A–E). This vaccine consists of inactivated dual-subtype (A plus D) FIV-infected cells, whereas its prototype vaccine consists of inactivated dual-subtype whole viruses. Both vaccines in experimental trials conferred moderate-to-substantial protection against heterologous strains from homologous and heterologous subtypes. Importantly, a recent case-control field study of Fel-O-Vax-vaccinated cats with outdoor access and ≥3 years of annual vaccine boost, resulted in a vaccine efficacy of 56% in Australia where subtype-A viruses prevail. Remarkably, this protection rate is far better than the protection rate of 31.2% observed in the best HIV-1 vaccine (RV144) trial. Current review describes the findings from the commercial and prototype vaccine trials and compares their immune correlates of protection. The studies described in this review demonstrate the overarching importance of ant-FIV T-cell immunity more than anti-FIV antibody immunity in affording protection. Thus, future efforts in developing the next generation FIV vaccine and the first effective HIV-1 vaccine should consider incorporating highly conserved protective T-cell epitopes together with the conserved protective B-cell epitopes, but without inducing adverse factors that eliminate efficacy.

show abstract

Section: Introductionmentioning

confidence: 99%

Lessons Learned in Developing a Commercial FIV Vaccine: The Immunity Required for an Effective HIV-1 Vaccine

Sahay

Yamamoto

2018

Viruses

View full text Add to dashboard Cite

show abstract

“…Using other routes of infection than the oro-nasal route or the concurrent administration of corticosteroids may introduce a bias in the assessment of vaccine efficacy. Although an oro-nasal challenge with a virulent FeLV strain is feasible as shown in our study, the intraperitoneal route or the simultaneous administration of glucocorticoids has frequently been used to increase the efficiency of FeLV challenge [20,24,28]. However, the route of infection may have an impact on the outcome of an infectious challenge and consequently on the efficacy of a vaccine candidate.…”

Section: Discussionmentioning

confidence: 83%

“…Efficacy data have been published for the different types of vaccines but few comparative studies are available [20]. In addition, most of the published studies rely on artificial challenge models, using the intra-peritoneal route or high doses of challenge virus with simultaneous administration of glucocorticoids [24]. Although less commonly performed, natural challenge models of infection are generally regarded as the most valuable method of assessing FeLV vaccine efficacy, mimicking natural infection as much as possible.…”

Section: Introductionmentioning

confidence: 99%

A Comparative Study of the Efficacy of a Canarypox Based Recombinant Leukemia Vaccine against a Natural Contact Felv Challenge in Cats

Sparkes¹,

Tasker

et al. 2015

J Vaccines Vaccin

View full text Add to dashboard Cite

Feline leukaemia virus (FeLV) infection is a major infectious disease of cats, but its prevalence has decreased as a result of management of infected animals and vaccination. Efficacy of vaccines is tested in vaccination/challenge experiments which are unfortunately poorly representative of the natural conditions of infection and may in some instances lead to biased conclusions. To overcome this limitation of traditional efficacy studies, we tested the efficacy of a non-adjuvanted recombinant canarypox-FeLV vaccine in a natural contact challenge model, and compared it to an adjuvanted commercially available vaccine. Methods Vaccinated and unvaccinated control cats were mixed with persistently viraemic cats and kept in close contact for more than 6 months. Cats were regularly tested for p27 antigenaemia and viraemia. Cats that were found positive for either p27 antigenaemia or viraemia for the last three blood samples were considered persistently viraemic. Results This contact challenge resulted in a high rate of persistent viraemia in control cats (78%). Vaccination efficiently protected cats against persistent viraemia with preventable fractions of 79% for the canarypox vectored vaccine and 68% for the adjuvanted commercial vaccine. Conclusion The natural contact challenge model proved to be a potent method to reproduce FeLV challenge, confirming that under appropriate conditions FeLV is efficiently transmitted. Despite the severity of the challenge, both vaccines provided a strong and sustained protection against persistent viraemia over a 6-month contact period. This study confirmed the efficacy of a non-adjuvanted canarypox-vectored FeLV vaccine against a contact challenge mimicking the natural conditions of infection.

show abstract

“…e read with interest the paper on the comparative efficacy of feline leukemia virus (FeLV) inactivated whole-virus vaccine and canarypox virus-vectored vaccine during virulent FeLV challenge and immunosuppression by Patel et al (1).…”

mentioning

confidence: 99%

Immunosuppression in a Comparative Study of Feline Leukemia Virus Vaccines

Poulet¹,

Jc²,

Masias

2015

Clin Vaccine Immunol

View full text Add to dashboard Cite

Comparative Efficacy of Feline Leukemia Virus (FeLV) Inactivated Whole-Virus Vaccine and Canarypox Virus-Vectored Vaccine during Virulent FeLV Challenge and Immunosuppression

Cited by 21 publications

References 23 publications

Lessons Learned in Developing a Commercial FIV Vaccine: The Immunity Required for an Effective HIV-1 Vaccine

Lessons Learned in Developing a Commercial FIV Vaccine: The Immunity Required for an Effective HIV-1 Vaccine

A Comparative Study of the Efficacy of a Canarypox Based Recombinant Leukemia Vaccine against a Natural Contact Felv Challenge in Cats

Immunosuppression in a Comparative Study of Feline Leukemia Virus Vaccines

Contact Info

Product

Resources

About