- Patients must obtain minimum qualifying symptom scores on the final two pre-treatment birch pollen exposure sessions (Visits 4 and 5) to be enrolled into the study. Minimum qualifying symptom scores are defined as a TSS of at least 12 out of a possible 24 and a NSS of at least 7 out of a possible 12 on at least one symptom diary card on each of Visits 4 and 5. Furthermore, a minimum priming criteria for NSS of 7 out of a possible 12, including a score of at least 2 for runny nose, on two diary cards during each of Visits 4 and 5, must be obtained.