Freeze-dried HDM-SLIT tablets provide maximal HDM allergen delivery and optimal potency
Sunday, March 4, 2018
South Hall A2 (Convention Center)
Katsuyo Ohashi-Doi, PhD, Weibin Du, Hirokazu Kito, Hiroshi Nakazawa, Kaare Lund, PhD
RATIONALE: Two types of HDM SLIT-tablet formulations are currently available, a freeze-dried formulation and a compressed formulation. The impact of formulation on tablet potency and effectiveness of allergen delivery was assessed.

METHODS: Three HDM-SLIT tablets, two freeze-dried (6SQ-HDM and 12SQ-HDM, respectively) and one compressed (300IR), were dissolved in assay buffer under controlled and identical conditions, and the total potency of solubilized HDM allergens was measured at various time points from 0-5 minutes by inhibition ELISA, using a pool of HDM allergic patients' sera.

RESULTS: The two freeze-dried HDM SLIT-tablets dissolved completely and reached full effective potency of solubilized HDM allergens within 15 seconds. The achieved potency was proportional to the relative nominal strengths (6SQ-HDM and 12SQ-HDM) of the freeze-dried tablets. In contrast, delivery of solubilized HDM allergens from the compressed tablet was slower and incomplete, even after five minutes in solution. In the time interval that corresponds to the recommended sublingual holding times, the release of HDM allergens was higher for both the 6SQ-HDM and 12SQ-HDM freeze-dried HDM SLIT-tablet compared to the compressed 300IR tablet.

CONCLUSIONS: Only the freeze-dried HDM SLIT-tablets provided fast and complete allergen delivery, and achieved full potency of soluble HDM allergens within the recommended sublingual holding time (one minute).