Efficacy, Safety and Tolerability of Sulthiame in Patients With Obstructive Sleep Apnea (OSA)

Primary objective: To evaluate the efficacy of 3 different doses of Sulthiame (STM) compared to placebo on sleep apnea activity in adult patients with moderate to severe obstructive sleep apnea (OSA) after at least 12 weeks of treatment at target dose

Secondary objectives: To evaluate the effect of 3 different doses of STM after at least 12 weeks of treatment at target dose in patients with moderate to severe OSA on apnea/hypopnea events, hypoxic burden, sleep quality, daytime sleepiness, patient's perception of symptoms and well-being, comorbidity-related outcomes and safety and tolerability of STM

Exploratory objective: To evaluate potential predictive biomarker (eg, blood gas analysis parameters or additional polysomnography [PSG] variables) with regard to efficacy

Key Inclusion Criteria:

• OSA diagnosis according to the International Classification of Sleep Disorders - Third Edition criteria with an AHI of ≥15 documented by PSG or polygraphy (PG).
• Currently not treated with continuous positive airway pressure (CPAP) or mandibular advancement device (MAD) due to patient-reported:
• non-tolerability; and/or
• non-compliance; and/or
• not willing to use CPAP or MAD (treatment-naïve patients)

Key Exclusion Criteria:

• Any OSA treatment within the last 4 weeks prior to screening
• Fulfill criteria for a dominant central sleep apnea syndrome or dominant Cheyne Stokes respiration
• Other clinically significant sleep disorder including periodic limb movement disorder, restless leg syndrome, periodic limb movement arousal index (PLMAI) of >15*, insomnia, parasomnia or narcolepsy

• as part of PSG baseline assessment
• Hypoventilation or hypoxemia due to chronic obstructive pulmonary disease or other respiratory condition
• Clinically relevant craniofacial malformation
• Any upper airway surgery for OSA within the last 12 months prior to baseline
• Patients who underwent an obesity surgery within the last 2 years prior to baseline or patients actively participating in any weight loss treatment program or use of any weight loss medication (prescription or over-the-counter) within 1 month prior to the first PSG night.