A comparison of two grass pollen extracts in the treatment of hay fever.

This trial of hyposensitisation compares the efficacy and safety of an alum absorbed 2-grass extract (Phleum pratense and Dactylis glomerata) with a traditional pyridine extracted alum precipitated 5-grass preparation whose efficacy has been demonstrated previously. 33 patients, (20 Alpare, 13 Allpyral), were entered into the trial which continued for 3 years; in the second year there were 17 Alpare and 11 Allpyral patients, and 13 Alpare and 10 Allpyral in the third year. Patients on Alpare required fewer dosage modifications due to adverse effects, but otherwise the treatments proved comparable. By the end of the second year, all patients achieved a significant increase of grass-specific IgG. There was no increase in total or specific IgE levels. Subjective assessment by both patients and physicians was in favour of Alpare in the first year, and a larger percentage of Alpare patients achieved a symptom-free summer in the second year. Analysis of daily diaries kept by patients during the grass pollen seasons showed that both treatments resulted in decreased use of medication year by year despite increasing pollen counts. We have shown that an extract made in accordance with modern requirements for purification and biological standardisation performed at least, as well as the older proven form of treatment.