Apnimed Provides Clinical Updates for Multiple Product Candidates

• First Patient Dosed in Phase 2A Dose-Finding, Proof-of-Concept RESTEADY Trial Evaluating SASS-001 in a Sub-Population of Patients with Sleep Apnea with a Central Component; Top-line Data Expected in 1H 2026
• SASS-001, a Novel Drug Combination of Sivopixant and a second compound, is the first clinical stage asset from Apnimed's Joint Venture with Shionogi
• Both Phase 3 Trials (SynAIRgy and LunAIRo) evaluating AD109 in Mild, Moderate and Severe Obstructive Sleep Apnea (OSA) patients of all body types remain on track for top-line results expected in Q2 and Q3 2025, respectively

CAMBRIDGE, Mass., April 7, 2025 /PRNewswire/ -- Apnimed, Inc., a pharmaceutical company building the industry-leading portfolio of first-in-class oral drug candidates that address the root causes of obstructive sleep apnea (OSA) and other sleep-related breathing diseases, today announced that the first patient has been dosed in the Phase 2A RESTEADY trial evaluating the novel oral drug combination, SASS-001, in an underserved population of patients suffering from sleep apnea with a central component. Top-line results from the study are expected in the first half of 2026. SASS-001 represents the first clinical stage asset from Shionogi-Apnimed Sleep Science, LLC (SASS), Apnimed's joint venture with Shionogi & Co., Ltd. (Shionogi).

"With the first patient dosed in the Phase 2A RESTEADY trial, both Apnimed and SASS have reached an important milestone – the advancement of a scientific hypothesis to clinical development," commented Larry Miller, MD, Chief Executive Officer of Apnimed. "Today's announcement represents the combined efforts of the Apnimed and Shionogi teams, highlighting their respective strengths in sleep medicine drug development and drug discovery."

RESTEADY is a Phase 2A, multicenter, double-blind randomized, controlled, dose escalation, parallel-arm, safety and efficacy study evaluating SASS-001 in adult patients suffering from sleep apnea with a central component (NCT06776432). The study is expected to enroll approximately 60 patients from up to 10 U.S. clinical sites. Patients will be randomized in a 3:1 ratio to either dose-escalating SASS-001 or a placebo arm. Patient participation in the study is approximately 10 weeks, with trial measures to include sleep-clinic polysomnography and at-home sleep evaluations.

Apnimed's most advanced clinical program, AD109, also continues to progress following the conclusion of enrollment in both Phase 3 clinical trials, LunAIRo and SynAIRgy. The Company continues to anticipate the availability of top-line data from both trials in Q2 and Q3 2025, respectively. AD109 is being studied in obese and non-obese adult patients with mild, moderate and severe OSA.

About SASS and SASS-001

SASS is a joint venture of Apnimed and Shionogi focused on accelerating the discovery, preclinical and clinical development of novel pharmacologic solutions designed to address the complex pathology of sleep apnea and other sleep related diseases. SASS-001 is an investigational oral clinical candidate under development by SASS for sleep apnea with a central component. The candidate is a combination of sivopixant, a selective P2X3 receptor antagonist, and a second compound.

About Sleep Apnea with a Central Component

Sleep apnea with a central component is characterized by the concomitant presence of obstructive and central apneas. In central apneas, breathing temporarily stops due to absence of the signal from the nervous system to respiratory muscles to initiate a breath. This mechanism is different from the neuromuscular dysfunction that is thought to cause OSA, in which a breath is initiated but airflow is prevented by a physical occlusion of the airway despite contraction of respiratory muscles. Central and obstructive apneas often coexist in an individual patient, particularly in those with concomitant cardiovascular diseases such as atrial fibrillation and heart failure.

About Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a serious, chronic sleep-related breathing disease in which the upper airway repeatedly collapses during sleep, leading to intermittent oxygen deprivation. It is caused by two overlapping mechanisms: neuromuscular dysfunction during sleep and predisposing anatomic abnormalities. It has been demonstrated that OSA affects people of all body types, ages and genders —there is no single "face" of the disease.  An estimated 80 million people in the United States and 1 billion people worldwide suffer from OSA. 

An individual with OSA can experience hundreds of sleep apnea events in a single night, each one reducing the blood oxygen levels and negatively impacting cellular functions vital to normal health and function. Failure to effectively treat OSA increases the risk of serious long-term health consequences, such as high blood pressure, cardiovascular disease and type 2 diabetes, along with impacts on quality of life, including daytime fatigue and impaired judgement. Yet, the majority of those diagnosed with OSA refuse, abandon, or underutilize treatment. Currently, no available pharmacological treatments directly address the underlying neuromuscular dysfunction that is present in all people with OSA.

About Apnimed

Apnimed is a privately held clinical-stage pharmaceutical company dedicated to transforming the treatment landscape for sleep-related breathing diseases. We believe the introduction of simple, once-nightly oral drugs will dramatically expand diagnosis and the reach of treatment for people with OSA. OSA, like other common chronic diseases such as diabetes or hypertension, would benefit from having multiple drugs with differing mechanisms to more fully address the heterogeneity of disease pathophysiology. Apnimed envisions a new era where novel oral therapies simplify intervention, expand the reach of diagnosis and treatment, and help more people get the oxygen and restorative sleep needed to thrive.

Based in Cambridge, Mass., Apnimed is advancing its growing pipeline of oral pharmaceutical product candidates designed to improve oxygenation in individuals living with OSA and other sleep-related breathing disorders. Our lead candidate AD109 could become the catalyst for a new oral treatment paradigm for OSA that has been historically limited to cumbersome devices or invasive surgeries. AD109 is currently in two Phase 3 clinical trials for the treatment of mild, moderate and severe OSA. Apnimed is developing several therapies through our joint venture with Shionogi & Co., Ltd., Shionogi Apnimed Sleep Science.

Learn more at apnimed.com or follow us on X and LinkedIn.

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Investor Contact:
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SOURCE Apnimed, Inc.