INTRODUCTION: The variability in the efficacy of allergen-specific immunotherapy (AIT) for nasal symptom control can be attributed to individual differences, to explore the hypothesis of systematic variability in AR symptom alleviation with AIT and to determine whether this variability correlates with AR severity, route of administration, treatment duration, age, or study publication year. METHODS: We reviewed randomized controlled trials (RCTs) of AIT for dust mite (DM)-induced AR, extracting data on baseline mean, endpoint mean, standard deviation (SD), and participant numbers. A random-slope mixed-effects model (RSMM) was employed to evaluate the differences in variability between the AIT and control groups, as well as to identify potential influencing factors. RESULTS: There was no significant difference in response variability between the AIT and control groups. The response variability to AIT was not associated with AR severity, route of administration, age, or year of publication. The cohort that underwent 36 months of AIT exhibited a higher degree of response variability compared to the group treated for 6 months. CONCLUSION: The present study did not identify systematic variability in individual response to AIT when measured by TNSS alone. More refined outcome measures and more associated factors are needed to explore personalized AIT in the future.