The trial results demonstrated that ACAM-FLU-A was well tolerated and capable of stimulating an immune response. Although immune responses were observed in all groups that received vaccine, the highest immune response was observed in the group vaccinated with ACAM-FLU-A plus QS-21 adjuvant. In this group, 90% of subjects generated virus-specific antibodies following immunization.
The Phase I trial of ACAM-FLU-A evaluated the vaccine’s safety and ability to generate an immune response among vaccinated subjects. The randomized, double-blind, placebo-controlled trial was conducted at multiple centers in the US and involved 79 subjects. The study consisted of four arms: ACAM-FLU-A alone, ACAM-FLU-A plus aluminum hydroxide adjuvant, ACAM-FLU-A plus QS-21 adjuvant, and placebo. Subjects in the trial received two doses of the treatment to which they had been randomized.
Under the terms of the agreement, Antigenics is entitled to receive future milestone payments and product royalties in the event of successful development and commercialization of ACAM-FLU-A. QS-21 is an investigational adjuvant, which is a substance added to vaccines and other immunotherapy that is designed to enhance the body’s immune response to the antigen contained within the treatment.
Garo Armen, chairman and CEO of Antigenics, said: “These findings continue to demonstrate the criticality of QS-21 as an adjuvant in a number of high-tech vaccine candidates.”