AVANT's Single-Dose Oral Ty800 Vaccine Meets Primary Endpoints in Phase 2 Study
Tuesday April 1, 8:00 am ET
NEEDHAM, Mass.--(BUSINESS WIRE)--AVANT Immunotherapeutics, Inc. (Nasdaq: AVAN - News) announced today that the double-blind, placebo-controlled multi-center Phase 2 clinical trial of its typhoid fever vaccine candidate, Ty800, met all primary endpoints. The Phase 2 study was an out-patient, dose-ranging clinical trial in 183 healthy volunteers that evaluated two dose levels of the Ty800 vaccine and followed each subject for six months post-vaccination. The endpoints of the Phase 2 study were to determine the optimal dose of Ty800 for further development based on the safety, reactogenicity, and immunogenicity of the vaccine.
Data from the trial showed that the single-dose, oral vaccine was well tolerated and immunogenic, demonstrating that the desired immune response was achieved. Incidence of reactogenicity symptoms and adverse events post-vaccination were similar to placebo. Importantly, immunogenic response was dose-dependent. Positive immune response or seroconversion (prospectively defined as a 4-fold increase in anti-LPS titers over pre-dose level) rates were 65.5% (36/55) and 80% (44/55) in the low and high dose groups, respectively, and was significantly (p<0.001) higher than placebo.
“The Ty800 data indicate that AVANT’s vaccine may have significant potential advantages over currently licensed vaccines, in term of safety, protectivity and ease of administration,” said Una S. Ryan, Ph.D., President and Chief Executive Officer of AVANT Immunotherapeutics, Inc. “Available vaccines are given by either single needle injection or three to four oral doses over the course of two weeks. We believe a more efficacious, single-dose oral typhoid fever vaccine could greatly expand the current markets for both travelers in developed countries and mass immunization programs in developing countries. The typhoid fever vaccine market currently has over $200 million in annual sales.”
AVANT is advancing its vaccine programs toward creating a “Super Combination Traveler’s Vaccine.” The “Super Vaccine” is designed to capture the potential of our single-dose oral delivery platforms to provide combined protection against multiple bacterial diseases including cholera, typhoid, ETEC (enterotoxigenic E. coli) and paratyphoid in one convenient and efficient vaccine for world travelers.
About the Ty800 Vaccine
AVANT has designed the Ty800 vaccine to offer rapid, oral, single-dose protection against Salmonella typhi, the cause of typhoid fever. The Ty800 vaccine was developed using genetic techniques to delete specific genes known to be essential to the virulence of S. typhi. The clinical trial was designed to show whether Ty800 is well tolerated in humans and rapidly elicit strong immune responses.
The Study
A total of 183 healthy adult volunteers were randomized at five centers across the US, including 60 subjects (120 total) assigned to each of the Ty800 dose levels, 1x108 and 1x109 colony-forming units (CFUs), and 63 subjects assigned to placebo control (buffer only). The volunteers were evenly divided among the three treatment groups in terms of age, gender, race, weight and height. The doses used in this study were immunogenic with similar safety and reactogenicity as placebo. Following vaccine administration, anti-LPS titers levels rose and were significantly (p<0.001) higher among Ty800 treated subjects compared to placebo controls at all timepoints tested. |
