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Trial record 1 of 1 for:    NCT03831971
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The Influence of ANS-6637 on Midazolam Pharmacokinetics in Healthy Volunteers

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT03831971
Recruitment Status : Completed
First Posted : February 6, 2019
Last Update Posted : January 2, 2020
National Institute of Allergy and Infectious Diseases (NIAID)
Information provided by (Responsible Party):
National Institutes of Health Clinical Center (CC)

Brief Summary:


Opioids are medicines that control pain. But they are often misused, which can lead to illness and death. Opioids increase dopamine to the brain, which makes people feel good and often causes them to crave drugs, leading to misuse and addiction. An investigational drug ANS-6637 may lower the dopamine surge and stop opioid craving. Midazolam is a drug approved for anxiety. Researchers want to give the two drugs together and see if ANS-6637 affects midazolam levels, to help understand how ANS-6637 is used in the body.


To study the safety, tolerability, and effects of ANS-6637 taken with and without midazolam.


Healthy adults 18 65 years old


Participants will be screened with a medical history, physical exam, and blood and heart tests. Participants who can get pregnant will have a pregnancy test.

Participants must agree to use 2 types of birth control during the study, if applicable.

Participants will stay at the clinic for 10 days. Meals will be provided. Participants will not be allowed to:

Leave NIH campus

Eat or drink anything with caffeine, alcohol, or certain juices

Use any nicotine or related products (including vaping)

Use any medicines (including herbal)

During the clinic stay, participants will:

Fast overnight several times

Have blood drawn most days. Twice, a small tube will be inserted in an arm vein for frequent blood samples.

Repeat screening tests and answer questions about their mood several times

Get midazolam syrup in water on 1 day

Take 6 ANS-6637 tablets by mouth on 5 days

Take both study drugs on 1 day

A few days later, participants will have a follow-up visit to repeat screening tests and answer questions about their mood.

Condition or disease Intervention/treatment Phase
Opiod Use Disorder Drug: ANS-6637 Phase 1

Detailed Description:

Opioid use causes a myriad of effects which contribute to significant morbidity and early mortality, and is associated with risky sexual behavior and injection drug use (IDU), two major forms of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) transmission in urban and suburban United States. Through these high-risk behaviors, persons with opioid use disorder (OUD) develop both direct comorbidities (e.g. blood stream infections and infectious endocarditis), as well as risk-associated illnesses (e.g. sexually transmitted infections, HCV and hepatitis B virus [HBV]) which have considerable downstream health care effects. As such, there is a need for pharmacologic agents in the treatment of OUD that go beyond avoidance of withdrawal and facilitate decreased frequency or complete cessation of opioid use.

The biologic mechanism of OUD, common to all forms of addiction, is a conditioned drug cue-related response in the CNS, causing a dopamine surge. If effective, a central pharmacologic strategy targeting the aberrant reward circuitry seen in OUD could potentially reduce drug craving and result in opioid abstinence.

In the SEARCH Pharmacokinetic (PK) investigation, we aim to understand the pharmacokinetic signal of the novel, oral agent ANS-6637, an aldehyde dehydrogenase 2 (ALDH-2) inhibitor that has the potential to reduce dopamine surge in the CNS and inhibit opioid craving. In preclinical studies, the active metabolite of ANS-6637, GS-548351, showed substrate dependent inhibition of CYP3A in vitro, with little or no inhibitory effect on the activities of other cytochrome P450 (CYP) enzymes. As such, the current investigation seeks to explore the potential inhibition of CYP3A by ANS-6637 with the FDA-recommended CYP3A probe substrate, midazolam.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 26 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: The Influence of ANS-6637 on Midazolam Pharmacokinetics in Healthy Volunteers (SEARCH PK)
Actual Study Start Date : March 1, 2019
Actual Primary Completion Date : August 9, 2019
Actual Study Completion Date : December 30, 2019

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: 1
Midazolam PK assessment before and after steadystate ANS-6637
Drug: ANS-6637
Subjects will receive (1) midazolam 5 mg po single dose on Day 1 followed by (2) Drug free period on Day 2 followed by (3) ANS-6637 600 mg po daily (Days 3-7) to reach steady state followed by (4) ANS-6637 600 mg po single dose + midazolam 5mg po single dose on Day 8

Primary Outcome Measures :
  1. The primary endpoints of this study will be assessed by characterization of plasma area under the concentration time curve0-infinity (AUC0-inf), maximum total plasma concentration (Cmax), time to maximum plasma concentration (tmax),apparent e... [ Time Frame: Day 1 and Day 8 ]
    Pharmacokinetics of midazolam before and after steady state ANS-6637

Secondary Outcome Measures :
  1. Number of Grade 1-4 adverse events, as defined by the DAIDS Toxicity Table Version 2.1, July, 2017 [ Time Frame: From Day 1 to completion of study participation. ]
    Evaluate the safety and tolerability of administration of ANS-6637 alone or in combination with MDZ.

  2. Plasma area under the concentration time curve 0-24 hours (AUC0-24), Plasma area under the concentration time curve 0-last quantifiable point (AUC0-last), time to maximum plasma concentration(tmax),apparent elimination rate constant (?Z), ter... [ Time Frame: Day 8 ]
    Describe the steady state pharmacokinetics of ANS- 6637 and GS-548351.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No


  1. Must have the ability to understand and must personally sign a written informed consent form, which must be obtained prior to initiation of study procedures.
  2. Must be between 18 and 65 years of age, inclusive.
  3. Must have discontinued use of nicotine and nicotine containing products including vaping or juuling from 90 days prior to study drug dosing and throughout the study duration.
  4. Must be willing to abstain from any food or beverages containing alcohol 72 hours prior to first dose and through follow-up visit.
  5. Must be willing to abstain from cannabis 72 hours prior to first dose and through follow-up visit.
  6. Must be willing to abstain from caffeine (including tea, coffee, chocolate) or grapefruit, Seville orange juice or other methyl xanthine containing foods (e.g. theophylline, theobromine, tea leaves, yerba mate, kola nuts and guarana berries) 72 hours prior to the first dose and through follow- up visit.
  7. Must have a body mass index (BMI) from 19 to 30 kg/m^2 (inclusive) at screening.
  8. Must be human immunodeficiency virus type 1 (HIV-1) antibody negative at screening.
  9. Must be hepatitis B (HBV) surface antigen negative at screening.
  10. Must be hepatitis C (HCV) antibody or RNA negative at screening.
  11. Male subjects must refrain from sperm donation from clinic admission, throughout the study period, and continuing for at least 90 days following the last dose of study drug.
  12. Subjects must refrain from blood donation from clinic admission, throughout the study period, and continuing for at least 30 days following the last dose of study drug.
  13. Must be willing to comply with contraception guidelines below Contraception:

    The fetal risks associated with ANS-6637 are not known, but pre- clinical animal data demonstrate some risk. Subjects must agree not to become pregnant or impregnate a female. Females of childbearing potential must have a reproductive risk assessment done to determine the risk of undetectable pregnancy at study start [i.e. sexual and contraceptive history for 30 days preceding screening] pregnancy test at screening and baseline (Day 0). For the duration of the study, subject and their partners must practice two non-hormonal methods of birth control, having begun no less than 30 days, without interruption, prior to screening. They must continue to use both methods until 3 months after stopping the study drug. Two of the three methods of birth control listed below MUST be used, or an alternative combination offering very high efficacy, per the PI, in consultation with the Sponsor Medical Monitor may be considered:

    • Male or female condoms [but not both] with a spermicide
    • Diaphragm with a spermicide
    • Intrauterine device (IUD)

    If pregnancy is suspected or should occur, subjects must notify the study staff immediately.

  14. Must, in the opinion of the Investigator, be in good health based upon medical history and physical examination, and screening laboratory evaluations.
  15. Judged to be healthy based on medical history, physical examination, vital signs, and clinical laboratory tests at screening and Day 0: liver function tests (AST, ALT, Tbili) less than or equal to upper limit of normal [ULN], platelets (PLT) >150,000/ microliter, hemoglobin (Hgb) >13 g/dL (males); >12 g/dL (females), CK less than or equal to 2x ULN, Amylase/lipase < ULN, thyroid function tests [TSH and T4] within normal range, fasting total cholesterol <240 mg/dL, or fasting triglycerides <240 mg/dL, per DAIDS AE table and Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Trials AE table for total bilirubin [Tbili] only.
  16. Must be willing and able to comply with all study requirements.


  1. Therapy with any prescription, over-the-counter (OTC), herbal, or holistic medications, including hormonal contraceptives by any route, within 5 half- lives of the agent prior to receipt of any study medications will not be permitted with the following exception: Intermittent or short-course therapy (<14 days) with prescription or OTC medications, herbals, or holistic medications within the screening period prior to starting study drugs may be permitted after review by the investigators on a case-by-case basis for potential drug interactions. Receipt of influenza vaccination will be allowed prior to, during, and/or after the study.
  2. Have any serious or active medical, surgical, or psychiatric conditions which, in the opinion of the Investigator, would interfere with subject treatment, assessment, or compliance with the protocol.
  3. Have previously participated in an investigational trial involving administration of any investigational compound within 30 days prior to screening.
  4. Have current, or a history of mild to severe alcohol use, cannabis or other substance use disorder including any use of illicit drugs as defined by DSM-5 criteria, within 12 months of first study dose
  5. Renal impairment (chronic renal insufficiency of any chronic kidney disease stage, or acute renal failure not induced by drug therapy defined as eGFR <90 ml/min)
  6. Have a positive urine drug test (ethanol, cannabis, barbiturates, cocaine, opiates, or amphetamines) at Screening or Day 0.
  7. History of flushing or intolerance related to alcohol consumption using the NIAAA screening assessment questionnaire tool for alcohol flushing
  8. Inability to obtain venous access for sample collection.
  9. Have a history of significant drug sensitivity or drug allergy to any benzodiazepines.
  10. Known hypersensitivity to formulation excipients: microcrystalline cellulose, croscarmellose sodium, magnesium stearate, polyvinyl alcohol, titanium dioxide, polyethylene glycol, and talc.
  11. Have been treated with systemic steroids, immunosuppressant therapies or chemotherapeutic agents within 3 months of study screening or expected to receive these agents during the study (e.g., corticosteroids, immunoglobulins, and other immune- or cytokine-based therapies).
  12. Presence or history of clinically significant cardiovascular disease, cardiomyopathy, and/or cardiac conduction abnormalities.
  13. Have clinically significant ECG abnormalities or any of the following ECG abnormalities at Screening: PR >220 msec; QRS >120 msec; QTcF >450 msec; HR <40 beats per minute; second or third degree heart block.
  14. Have a history or family history of Long QT Syndrome, Brugada syndrome, Wolfe-Parkinson-White Syndrome, or have a family history of sudden cardiac death or unexplained death in an otherwise healthy individual between the ages of 1 and 30 years.
  15. Have history of syncope, palpitations, unexplained dizziness or chronic nausea or headaches.
  16. Have an implanted defibrillator or pacemaker.
  17. Have a history of liver disease, including Gilbert's Disease.
  18. Any clinically significant electrolyte abnormality (outside of NIH normal reference ranges) at screening (e.g., hypokalemia, hypocalcemia, hypomagnesemia) or any condition that could lead to abnormal electrolyte disturbances (eg, eating disorder).
  19. Have a history of taking dopamine antagonists/anti-psychotics.
  20. Are unable to comply with study requirements.
  21. Positive urine toxicology screen

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03831971

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United States, Maryland
National Institutes of Health Clinical Center
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Institutes of Health Clinical Center (CC)
National Institute of Allergy and Infectious Diseases (NIAID)
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Principal Investigator: Henry Masur, M.D. National Institutes of Health Clinical Center (CC)
Additional Information:
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Responsible Party: National Institutes of Health Clinical Center (CC) Identifier: NCT03831971    
Other Study ID Numbers: 190052
First Posted: February 6, 2019    Key Record Dates
Last Update Posted: January 2, 2020
Last Verified: December 30, 2019

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by National Institutes of Health Clinical Center (CC):
Reward Pathway
Opioid Use