Apnimed's Sulthiame Shows Promise in Phase 2 Trial for Obstructive Sleep Apnea, Results Published in The Lancet
Key Insights
Apnimed (search)'s Phase 2 FLOW study of sulthiame, an oral carbonic anhydrase (search) inhibitor, met its primary endpoint across all doses in treating moderate to severe obstructive sleep apnea (search).
The 15-week trial enrolled 298 patients across 28 European sites and demonstrated significant dose-dependent reductions in breathing disturbances and improved nocturnal oxygenation.
Sulthiame was generally well-tolerated with a favorable safety profile, offering a distinct mechanism of action from other investigational OSA (search) treatments.
Apnimed (search) announced the publication of positive Phase 2 results for sulthiame in The Lancet, demonstrating the oral carbonic anhydrase (search) inhibitor's efficacy in treating obstructive sleep apnea (search) (OSA (search)). The FLOW study met its primary endpoint across all tested doses, showing significant improvements in multiple efficacy measures while maintaining a favorable safety profile.
Phase 2 FLOW Study Results
The multicenter, randomized, double-blind, placebo-controlled trial evaluated three dosages of sulthiame (100 mg, 200 mg, and 300 mg) administered once daily at bedtime for 15 weeks. The study enrolled 298 adult patients with untreated, moderate to severe OSA (search) across 28 sites in five European countries.
The primary endpoint, relative change in the apnea-hypopnea index (AHI3a) from baseline to Week 15, was met for all sulthiame doses. A dose-response effect was identified and well-characterized across the treatment groups.
Key findings from the study included significant reduction in OSA (search) severity, with all sulthiame doses demonstrating a consistent and dose-dependent reduction in breathing disturbances as measured by AHI3a. The treatment also led to significant improvements in oxygen desaturation index (ODI) and mean overnight oxygen saturation, indicating improved nocturnal oxygenation.
Safety Profile and Tolerability
Sulthiame was generally well-tolerated throughout the 15-week treatment period. Adverse events were consistent with prior experience and the known pharmacology of carbonic anhydrase (search) inhibitors. Most adverse events were mild or moderate and dose-dependent, supporting the drug's potential for further clinical development.
Distinct Mechanism of Action
"The positive data from the FLOW trial confirm previous proof-of-concept study results and suggest that sulthiame offers the potential to treat obstructive sleep apnea (search) with a mechanism of action that is distinct from other investigational drugs, including that of our lead asset AD109," said Larry Miller, M.D., CEO of Apnimed (search).
Sulthiame is designed to restore nighttime breathing stability, addressing a contributing mechanism in people with OSA (search). The drug has successfully completed two Phase 2 trials in over 300 European OSA patients, studied for durations of up to 3 months.
Partnership and Development
Apnimed (search) is developing sulthiame in partnership with Shionogi & Co., Ltd., through their joint venture, Shionogi-Apnimed Sleep Science (search) (SASS (search)). The company previously acquired the intellectual property and exclusive global rights to develop and commercialize sulthiame from Desitin Arzneimittel GmbH.
Addressing Unmet Medical Need
OSA (search) affects an estimated more than 80 million people in the United States and nearly one billion people worldwide. The condition is caused by two overlapping mechanisms: neuromuscular dysfunction during sleep and predisposing anatomic abnormalities. Up to 80% of people living with OSA are undiagnosed and therefore untreated.
Currently, no available pharmacological treatments directly address the underlying neuromuscular dysfunction present in OSA (search). The majority of those diagnosed with OSA refuse, abandon, or underutilize existing treatments, which are historically limited to cumbersome devices or invasive surgeries.
Miller emphasized the need for multiple therapeutic approaches: "Multiple mechanisms and approaches are needed if we are to effectively tackle the large prevalence, complexity and heterogeneity of OSA (search). We are thrilled to have these compelling data published in a peer reviewed scientific journal as prestigious as The Lancet, and are particularly encouraged by the consistent improvements seen across multiple efficacy measures."