Immunotherapy with short ragweed fraction A:D-glutamic acid:D-lysine polymer in ragweed hay fever

We report the first human trial of immunotherapy employing the nonimmunogenic carrier, D-glutamic acid:D-lysine linked to short ragweed (SRW) fraction A (fraction A:D-GL). Twelve SRW-sensitive patients with no immunotherapy during the previous 19 yr received a 2-mo (7/79 to 9/79) course of fraction A:D-GL (average dose 49.5 mg, range 21 to 78 mg). We compared their symptom scores and serologic changes with two control groups of SRW-sensitive patients. Patients receiving fraction A:D-GL demonstrated at least a tenfold decrease in skin-test sensitivity to SRW and had statistically lower mean seasonal symptom scores (p less than 0.02) than untreated controls. Mean seasonal symptom scored did not differ statistically from those of control patients on year 4 of immunotherapy. In contrast to the expected suppression of IgE, we found that fraction A:D-GL stimulated both IgE and IgG responses to SRW and SRW-antigen E. These increases in IgE and IgG antibodies were significantly greater than in the control groups and appeared to be due largely to injection of fraction A:D-GL. Though fraction A:D-GL was generally well tolerated, we noted mild generalized urticaria in three patients, and large local reactions in five others. The difference between our results and the earlier results in mice may reside in the particular characteristics of this preparation of fraction A:D-GL.