Using Vaxfectin in conjunction with vaccines has increased immune responses against targets including H5N1, measles and cancer. Vical hopes the broad applicability of the adjuvant, coupled to other characteristics, will make it a universal tool for dose sparing and immune enhancement.
A review of Vaxfectin has been published in Expert Opinion on Drug Delivery to assess data from research into the adjuvant. “Vaxfectin has effectively boosted the immune response against a range of pDNA-expressed pathogenic antigens in preclinical models”, according to the review.
For instance, pDNA vaccines formulated with Vaxfectin have enhanced immunogenicity against cytomegalovirus, measles and H5N1 in rodents, non-human primates and ferrets respectively.
Vical concluded Vaxfectin-formulated DNA vaccines increase antibody response, elicit strong T-cell responses and can protect against lethal viral challenge on the basis of the research.
In September Vical’s share price dropped when the failure of a late-stage compound to meet the primary endpoint was followed by unveiling of plans to sell shares in an offering to the public.
Use against cancer
Vaxfectin has also been formulated with a Class I-restricted peptide of a tumour antigen tyrosinase-related protein 2 (TRP-2180-188) to evaluate its effectiveness against cancer.
Use of Vaxfectin increased T-cell response 70-fold compared to peptide without adjuvant. A 7-fold increased in response was seen in comparison to vaccine formulated with Freund’s adjuvant, a solution of antigen emulsified in mineral oil.
Furthermore, mice treated with the vaccine had a significantly increased survival rate compared to the untreated control.
Adjuvant production
“Ease of formulation, stability and low manufacturing costs” are other attractive characteristics of Vaxfectin, said Alain Rolland, executive vice president of product development at Vical.
The novel synthetic adjuvant was identified by Vical through screening of its cationic lipid library.