Pollinex® Quattro Ragweed: safety evaluation of a new allergy vaccine adjuvanted with monophosphoryl lipid A (MPL®) for the treatment of ragweed pollen allergy

Abstract

A novel allergy vaccine (Pollinex Quattro Ragweed) has been developed for the prevention or relief of allergic symptoms caused by pollen from Ambrosia spp. (ragweed). An extract from the pollen (chemically modified by glutaraldehyde) is adsorbed onto l-tyrosine with addition of the immunostimulatory adjuvant, monophosphoryl lipid A (MPL). A specific preclinical safety testing strategy was developed to support clinical use and comprised reference to preclinical data available for the marketed non-MPL adjuvanted form of the ragweed vaccine (Pollinex R) and a new repeat dose toxicity study in the rat. Studies with Pollinex R comprised single dose subcutaneous toxicity studies in mice and rats, repeat dose (10 injections over 20 days) parenteral toxicity studies in rats and dogs, an in vitro gene mutation assay along with single and multiple injection local tolerance studies in rats and dogs. The repeat dose subcutaneous toxicity study with Pollinex Quattro Ragweed involved seven injections over 3 weeks (which was more aggressive than the four weekly doses used in the clinic) with dose levels of up to 0.5 ml per animal used. Overall, the product showed no toxicological findings of significance at levels greatly in excess of those proposed for clinical use. As is a feature with vaccination, some dose site irritation was seen.