Appili releases tularemia vaccine results

Executive Summary

• Appili Therapeutics published a manuscript in the journal Vaccine demonstrating the efficacy of its biodefence vaccine candidate, ATI-1701, against tularemia.
• The study provides robust preclinical data showing durable protection in both rat and non-human primate (cynomolgus macaque) models against lethal aerosol exposure.
• The findings support the continued development of ATI-1701 in partnership with the U.S. Department of Defense, addressing a significant unmet medical need as there are currently no approved vaccines for tularemia in major global markets.

Key Details

• Publication Details: Manuscript titled "Vaccination with a novel live attenuated strain of Francisella tularensis subsp. tularensis protects cynomolgus macaques against aerosol F. tularensis infection" published in the journal Vaccine.
• Lead Author: Dr. Carl Gelhaus, Director of Non-Clinical Research at Appili, co-authored with researchers from institutions in the U.S., Canada, and Sweden.
• Rat Model Results:
  • Achieved 100% survival in rats challenged with aerosolized F. tularensis SCHU S4.
  • Protection was observed up to one year post-vaccination.
  • Efficacy maintained even at challenge doses exceeding 10,000 times the median lethal dose (LD50).
• Non-Human Primate Results:
  • Demonstrated up to 100% protection in cynomolgus macaques.
  • Showed reduced disease severity and improved histopathological outcomes.
• Immunogenicity: Immunized animals exhibited robust, dose-dependent, and long-lasting antibody responses (antigen-specific antibody titers) correlating with survival.
• Strategic Context: ATI-1701 is a first-in-class live attenuated vaccine candidate. Tularemia is a Category A pathogen considered a top biodefence priority. The U.S. Department of Defense is a key partner in the vaccine's development.

Notable Quotes

• "This publication marks a significant milestone in the development of ATI-1701 and adds to the growing body of evidence supporting its protective potential... Protection was dose-dependent, long lasting and associated with robust immune responses, including strong antigen-specific antibody titers." — Dr. Carl Gelhaus, Director of Non-Clinical Research, Appili Therapeutics.