Patient-centered and Neurocognitive Outcomes with Acetazolamide for Sleep Apnea

Patient-centered and Neurocognitive Outcomes with Acetazolamide for Sleep Apnea (NCT05804084) is a Phase 2 interventional studying Obstructive Sleep Apnea, sponsored by University of California, San Diego. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

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. Ultimately, this work promises a drug therapy option for millions of OSA patients who are unable to tolerate current treatments

What Stage of Research Is This?

Phase 2 trials evaluate whether a treatment actually works against Obstructive Sleep Apnea and continue monitoring side effects. Phase 2 enrolls larger groups (typically 100–300 patients) and produces the first real efficacy signal. A successful Phase 2 readout is what unlocks the much larger Phase 3 confirmatory trials needed for FDA approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 60 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Obstructive Sleep Apnea subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.

Who May Be Eligible (Plain English)

Who May Qualify: - Age ≥18 years - Body mass index ≤ 35 kg/m2 - Untreated moderate/severe OSA (AHI ≥15/h) Who Should NOT Join This Trial: - 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) - Prisoners - 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 Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

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) * Prisoners * 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

Treatments Being Tested

DRUG

Acetazolamide

Acetazolamide tablet (encapsulated)

DRUG

Placebo

Sugar capsule manufactured to match encapsulated Acetazolamide

Locations (1)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

UC San Diego; Altman Clinical and Translational Research Institute Building

La Jolla, California, United States

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05804084), the sponsor (University of California, San Diego), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05804084 clinical trial studying?

Who can participate in NCT05804084?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05804084?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05804084. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05804084. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.