Hemodilution therapy with hydroxyethyl starch solution (130/0.4) in unilateral idiopathic sudden sensorineural hearing loss:: A dose-finding, double-blind, placebo-controlled, international multicenter trial with 210 patients

Objective: Obtain and analyze first data on hydroxyethyl starch (HES 130/0.4) as monotherapy in acute idiopathic sudden sensorineural hearing loss (ISSNHL). Design: Randomized, double-blind, Phase-II, dose-finding study. Setting: Twenty-five ENT centers in Germany, the Czech Republic, Romania, and Austria. Patients: Two hundred and ten inpatients with first-time ISSNHL of at least 20 dB at two or more frequencies and 95 dB or less at all of the speech frequencies (0.5, 1.0, 2.0, 3.0, and 4.0 kHz) with respect to the other (normal) ear for up to 7 days (d). Intervention: Infusion of 750 mL/d with 45 (Group H), 30 (Group M), or 15 g/d HES (Group L), or glucose 5% (Group G) acting as placebo control during 6 days. Main Endpoint: Gain in average auditory threshold (in dB) from baseline to Day 7. Results (Medians): Average hearing loss at baseline was 24 dB, and infusions started 2 days after ISSNHL onset. No relevant group difference was observed in hearing gain or adverse treatment events, including pruritus. Half of all patients recovered completely by Day 7. Secondary Analysis: In patients who started treatment within 2 days after the onset of symptoms and who had systolic blood pressure (RRsyst) of less than 140 mm Hg, hearing at Day 90 had improved in all 28 cases under glucose 5%; for those who started treatment later and/or had RRsyst of 140 mm Hg or more, the risk for failing to recover under placebo was 29.2% (7/24). Comparing all 118 (51.9%) of 208 patients at such risk, outcome at Day 7 was markedly better in all HES subgroups than in the G subgroup (n(H):n(M):n(L):n(G) = 32:29:32:24, Kruskal-Wallis, p = 0.0221). Conclusion: All treatment groups were equivalent, including adverse treatment events. The secondary analysis showed that ISSNHL patients at risk for not improving under placebo (i.e., patients who started treatment more than 48 It after ISSNHL onset and/or with elevated RRsyst) recovered markedly better under infusions of HES 130/0.4.