Evaluation of the safety profile of the ASFV vaccine candidate ASFV-G-I177L

Authors: XUAN, TRAN - Navetco National Veterinary Joint Stock Company; LE THI THU, PHUONG - Navetco National Veterinary Joint Stock Company; NGUYEN QUANG, HUY - Navetco National Veterinary Joint Stock Company; DO THANH, THUY - Navetco National Veterinary Joint Stock Company; NGUYEN VAN, DUNG - Navetco National Veterinary Joint Stock Company; PHAM HÀO, QUANG - Navetco National Veterinary Joint Stock Company; QUÁCH VÕ, NGÔN - Navetco National Veterinary Joint Stock Company; Gay, Cyril; Gladue, Douglas; Borca, Manuel

Submitted to: Viruses
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/20/2022
Publication Date: 4/25/2022
Citation: Xuan, T., Le Thi Thu, P., Nguyen Quang, H., Do Thanh, T., Nguyen Van, D., Pham Hào, Q., Quách Võ, N., Gay, C.G., Gladue, D.P., Borca, M.V. 2022. Evaluation of the safety profile of the ASFV vaccine candidate ASFV-G-I177L. Viruses. https://doi.org/10.3390/v14050896.
DOI: https://doi.org/10.3390/v14050896

Interpretive Summary: African swine fever virus (ASFV) causes a devastating disease in swine, called African swine fever (ASF), that is currently spreading across Europe and Asia. There is no available vaccine for ASF, and currently only experimental live attenuated vaccines are derived from deletions of individual genes in the ASFV genome. here we describe some additional tests for one of our vaccine candidates that is required for regulatory approval.

Technical Abstract: African swine fever (ASF) is the cause of a recent pandemic that is posing a threat to much of the world swine production. The etiological agent, ASF virus (ASFV), infects domestic and wild swine producing a variety of clinical presentations depending on the virus strain and the genetic background of the pigs infected. No commercial vaccine for ASF is currently available although some recombinant live attenuated vaccines candidates have shown promising results. In addi-tion to determining vaccine efficacy, it is paramount to evaluate the safety profile of a live at-tenuated vaccine thoroughly in a variety of different conditions. To ensure that in different situ-ations the same level of efficacy and safety remain including testing the genome stability and possibility of reversion to virulence should the vaccine have the chance to evolve in animals, a study that is required for any live-attenuated vaccine to be used in the field. Here we evaluate these situations for a live attenuated vaccine candidate, ASFV-G-'I177L. Results from a re-version to virulence study showed that ASFV-G-'I177L remains genetically stable and pheno-typically the same as the master seed vaccine during five passages in swine In addition, large scale experiments to detect virus shedding and transmission were conducted these studies con-firmed that even under varying conditions, ASFV-G-'I177L is a safe live attenuated vaccine.