Quillaja brasiliensis saponins are less toxic than Quil A and have similar properties when used as an adjuvant for a viral antigen preparation

► Quillaja brasiliensis saponins (QB-90U) are less haemolytic and cytotoxic than Quil A. ► QB-90U significantly strengthens the vaccine humoral response in mice. ► The use of QB-90U as adjuvant induces a cellular immune response in mice. ► QB-90U is an adjuvant as effective as Quil A towards a viral antigen.