Comparison of polymerized and unpolymerized antigen E for immunotherapy of ragweed allergy.

Polymerization of ragweed antigen into high-molecular-weight polymers could improve immunotherapy for ragweed pollinosis by reducing side effects while retaining immunogenicity. To study this thesis, 23 ragweed-sensitive patients were treated with either ordinary ragweed antigen E or ragweed antingen E polymerized by glutaraldehyde. Four patients received the polymerized antigen, and six controls ordinary antigen according to the standard immunotherapy schedule; two groups of three patients received either form by a "doubling-dose" schedule. Seven subjects received the polymerized antigen by a schedule in which each successive dose was tripled. Serum antigen E binding capacity (blocking antibody) increased significantly in all subjects (P less than 0.001 by Student-test). Patients treated with polymerized antigen had fewer local and generalized reactions than those receiving the monomeric preparation. Polymerized ragweed antigen permits more rapid immunization of atopic persons, with fewer side effects than standard monomeric preparations.