Polymerized whole ragweed: An improved method of immunotherapy

Abstract

A single-blind study compared the effectiveness of glutaraldehyde-treated polymerized ragweed with nonpolymerized monomeric ragweed. These studies are an extension of those previously reported for polymerized AgE using a readily available ragweed preparation containing all ragweed antigens. Nineteen ragweed-sensitive patients were randomized into 2 groups; 10 received the polymerized form and 9 received the monomeric form. Four parameters were followed: serum-specific IgE against antigen E, total blocking antibody against antigen E, local and systemic reactions to injection therapy, and symptom score indices. Pretreatment levels of antigen E-specific IgE and blocking antibody activity were similar in both groups. After a total of 15,000 protein nitrogen units (PNU) had been given, blocking antibody activity in the monomer group rose from a mean of 173 ng AgE bound per ml to a mean of 2,813. The rise in blocking antibody activity in the polymer group was from a mean of 181 ng AgE bound per ml to 1,574. At 15,000 PNU, blocking antibody activity levels were not statistically different in the 2 groups. After 1 year of treatment, no consistent decrease in postseasonal specific IgE rise could be shown in either group. Forty times less erythema and 15 times less induration were found with polymerized ragweed. There were 7 systemic reactions with the monomer and none with the polymer. Both groups experienced symptomatic improvement with treatment.