NCT05804084 · University of California, San Diego
Patient-centered and Neurocognitive Outcomes With Acetazolamide for Sleep Apnea
(PANACEA)
What this study is about
Obstructive sleep apnea (OSA) is a severe type of snoring causing people to choke in their sleep. It affects millions of Americans, causing many health problems. For example, patients with OSA often feel very sleepy and are at risk of falling asleep while driving. OSA also causes elevated blood pressure, memory problems and can severely affect quality of life.
View original scientific description
Obstructive sleep apnea (OSA) is a severe type of snoring causing people to choke in their sleep. It affects millions of Americans, causing many health problems. For example, patients with OSA often feel very sleepy and are at risk of falling asleep while driving. OSA also causes elevated blood pressure, memory problems and can severely affect quality of life. Patients with OSA are often treated with a face-mask that helps them breath at night but can be difficult to tolerate. In fact, about half the patients eventually stop using this mask. Because there are few other treatments (and no drug therapy), many OSA patients are still untreated. Acetazolamide (a mild diuretic drug) has been used for over 50 years to treat many different conditions and is well tolerated. Recent data suggest, that acetazolamide may help OSA patients to not choke in their sleep and lower their blood pressure. Further, its low cost (66¢/day) and once-daily dosing may be attractive for OSA patients unable or unwilling to wear a mask each night. But previous studies had many limitations such as studying acetazolamide for only a few days and not capturing important outcomes. The goal of this study is to test if acetazolamide can improve sleep apnea, neurocognitive function and quality of life in adults with OSA, and to assess how it does that. Thus, the investigators will treat 60 OSA patients with acetazolamide or placebo for 4 weeks each. The order in which participants receive the drug or placebo will be randomized. At the end of each 4 week period the investigators will assess OSA severity, neurocognitive function and quality of life. Thus, this study will help assess acetazolamide's potential value for OSA treatment, and may also help to identify patients who are most likely to respond to acetazolamide.
Interventions
DRUG
Acetazolamide
Acetazolamide tablet (encapsulated)
DRUG
Placebo
Sugar capsule manufactured to match encapsulated Acetazolamide
Primary outcome measures
Apnea Hypopnea Index (AHI)
Time frame: 4 weeks
The AHI is a measure of sleep apnea severity and is defined as the number of apneas (no breathing for 10+ seconds) and hypopneas (reduced breathing for 10+ seconds associated with a \>=3% desaturation or cortical arousal) per hour of sleep. Alternative definitions of the AHI will be explored as well (e.g. hypopneas based on 4% desaturations, or position/sleep-stage specific AHIs).
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Age ≥18 years
- Body mass index ≤ 35 kg/m2
- Untreated moderate/severe OSA (AHI ≥15/h)
Exclusion criteria
- Substantial sleep hypoxemia (SpO2\<80% for \>10% of the monitoring time during the home sleep test, or for \>25% of the total sleep time during any of the in-laboratory studies)
- Abnormally low blood counts/electrolytes or renal function at baseline
- Use of OSA therapy during the past 1 month, or plans to urgently resume/(re)start clinical OSA therapy within 3 months
- Significant, uncontrolled cardiac, pulmonary, endocrine, renal, hepatic, neurocognitive, psychiatric, or urologic (e.g., kidney stones) disorder
- Other major sleep disorder (e.g., narcolepsy)
- Urgent need to initiate effective OSA therapy (i.e., Epworth sleepiness score \>18, commercial driver, prior sleep-related car accident, or based on MD judgment)
- Severe allergy to sulfa-drugs or taking another carbonic-anhydrase inhibitor (e.g., topiramate)
- Pregnancy/breastfeeding (current/planned)
- Illicit substance abuse or \>2 standard drinks of alcohol/day
- Medications that may affect OSA or ventilatory control (e.g., opiates, sedatives)
- Thiazide/loop diuretic (risk of hypokalemia)
- Inability to give consent or follow procedures
- Safety concern based on MD judgment
Where
- La Jolla, California
Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 8, 2026 · Source of record for eligibility and locations