The goal of this clinical trial is to learn if, how, and for whom suvorexant (SUV) works to treat alcohol use disorder (AUD). The main questions it aims to answer are:

• Is SUV effective for AUD?
• Does SUV dampen stress reactivity?
• Can the researchers develop a biomarker for SUV treatment response?

Researchers will compare SUV to a placebo (a look-alike substance that contains no drug) to see if drug SUV works to treat AUD.

Participants will:

• Take 10mg capsules of SUV or a placebo orally each night before bedtime for 8-weeks.
• Visit the laboratory before (baseline), 4-weeks (mid-point), and 8-weeks (end-point) after taking SUV or placebo that include the psychophysiological stress paradigm (electromyography; EMG).
• Complete daily reports of medication adherence, side-effects, sleep, alcohol use, and mood will be collected via smartphones during the 8-week medication trial.

Inclusion Criteria:

• Generally medically and neurologically healthy;
• Age 18 to 65 at the time of consent;
• Willing and able to give informed consent;
• Current DSM-5 diagnosis of moderate to severe alcohol use disorder;
• Engages in heavy alcohol use defined as drinking ≥14 standard drinks per week if male, and ≥7 standard drinks per week if female;
• Self-reported treatment-seeking for alcohol use disorder

Exclusion Criteria:

• Clinically significant medical or neurologic condition or neurocognitive dysfunction that would affect function, and/or task performance, and/or interfere with the study protocol, and/or be contraindicated for suvorexant including sleep disorders (e.g., narcolepsy; severe obstructive sleep apnea), hepatic impairment, compromised respiratory function, renal impairment, and endocrine disorders;
• Lifetime DSM-5 diagnosis of schizophrenia, bipolar disorder, or any psychotic disorder;
• Current substance use disorder (SUD) other than alcohol or mild cannabis use disorder;
• Currently pregnant (positive pregnancy test), lactating, or not agreeing to use birth control methods during the duration of the trial (women);
• Any use of medications for alcohol use disorder or any psychotropic medications (e.g., psychostimulants and benzodiazepines, some antidepressants);
• Current antihistamines use or medication use that may increase risk including, prescribed, over-the-counter, and herbal preparations, as determined by the study physician;
• Current use of strong or moderate inhibitors of CYP3A liver enzymes;
• Current use of strong CYP3A inducers;
• Current use of digoxin;
• Liver function tests more than 3 times the upper limit of normal or elevated bilirubin;
• Engages in night shift work;
• Smoke 10 or more cigarettes (or electronic equivalent) per day and are thus susceptible to acute nicotine withdrawal during lab visits;
• Obesity as defined by a body-mass index (BMI) equal or greater than 30, as calculated from weight and height self-report;
• Clinically significant alcohol withdrawal symptoms the day of the lab sessions, defined as a score >10 on the Clinical Institute Withdrawal Assessment of Alcohol Scale Revised (CIWA-Ar);
• Unwilling/unable to sign the informed consent document;
• Under 18 years old or over 65 years old at the time of enrollment;
• Have attempted suicide in the past 3 years and/or have current suicidal ideation determined as greater than moderate via the Columbia Suicide Severity Rating Scale (C-SSRS)

De-identified data from this project will be submitted to the NIAAA Data Archive (NDA) at the subject level along with appropriate supporting documentation to enable efficient use of the data by the research community. The investigators will follow instructions as discussed in the NIAAA Data Archive Data Sharing Terms and Conditions.

The data will be submitted to the NIAAA Data Archive biannually per NIAAA requirements throughout the duration of the study.