Clinical Efficacy of a Recombinant Grass Pollen Vaccine One Year after a 4 Month Treatment Course

Abstract

Immediate and sustained clinical efficacy of a recombinant grass pollen vaccine (BM32) consisting of IgE epitope peptides of Phl p 1, 2, 5 and 6 was evaluated in terms of optimized treatment schedule of a 4 month pre- seasonal treatment in grass pollen allergic patients (NCT02643641). Four treatment schedules (3, 4, 5 times active vs. Placebo) of BM32 were evaluated during grass pollen seasons 2016 and 2017. Symptom Scores (SS), Medication Scores (MS) and Combined Scores (SMS) of actively treated subjects were compared to placebo. In 2016 scores were correlated with symptoms (TNSS) in the challenge chamber. Symptoms and medication intake were reported daily during entire grass pollen season. SS was reported on a four point scale comprising 4 nasal symptoms (runny nose, blocked nose, sneezing, itchy nose) and 2 ocular symptoms (itchy/red eyes, and watery eyes). It was calculated as the sum of scores divided by 6. In the MS score values were assigned to categories of medication and calculated as predefined in the protocol. 124 subjects were included in the full analysis set. The mean daily SMS during the pollen peak immediately after treatment with 3, 4 or 5 injections of BM32 improved by 15%, 3% and 25 % vs. Placebo. During the grass pollen peak 2017 no further treatment effect could be demonstrated. Correlation coefficient of TNSS in the challenge chamber and SS during season 2016 was .5. Five active injections demonstrated the best immediate clinical efficacy, but no sustained effect. BM32 was safe and well tolerated.