Use of Sodium Channel Blocker to Relieve Dryness in Sjögren's

Objectives: To evaluate the safety and efficacy of an oral rinse formulation of 552 02, a novel epithelial sodium channel blocker, administered daily for 28 days in patients with primary Sjögren's syndrome Methods: This was a phase 2, exploratory, randomized, double-blind, placebo-controlled, crossover study of an oral rinse formulation of 552-02 versus placebo in 30 patients with primary Sjögren's syndrome. Following a screening period of up to 14 days, patients who met the inclusion and exclusion criteria were randomized to a crossover sequence of study drug and placebo, each administered for 28 consecutive days separated by a 28-day washout period. Patients received 552-02 delivered in 6 doses to the oral mucosa over the course of 12 hours. A final 7-day washout period preceded the study discharge visit.

Results: A total of 30 patients were randomized, and all 30 patients completed both treatment periods (552 02 and placebo treatments). Significant differences between the two treatments were noted for predose changes from baseline in mouth dryness on Day 7 (p=0.039) and Day 28 (p=0.033) and the ability to sleep on Day 28 (p=0.042). The Day 28 predose difference between treatments in global assessment of dry mouth and the assessment of tongue dryness both approached statistical significance (p=0.056 for both variables). No clinically relevant differences between the 2 treatment groups were noted for adverse events, clinical laboratory parameters, vital signs, or physical examination findings.

Conclusion:Overall, 552-02 was safe and well tolerated when administered six times daily for 28 days to patients with Sjögren's syndrome. Despite the small sample size, patients' assessments of changes from baseline in symptoms of dry mouth using visual analog scales indicated 552-02 efficacy for improvement in mouth dryness, tongue dryness, and the ability to sleep.(This study was funded by a grant from Parion, Inc.)