ClinicalTrials.gg
RecruitingNCT05120934MACS-2Updated Jan 21, 2026

Efficacy of Two Doses of Duloxetine & Amitriptyline in Interstitial Lung Disease-related Cough

A Phase 2 interventional study of Amitriptyline 25 MG and Amitriptyline 50 MG in Interstitial Lung Disease, sponsored by Mayo Clinic. Recruiting at 1 site in United States. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-01-21.

Sponsored by Mayo Clinic · Phase 2, Interventional, and Treatment

From the registry’s dates

  • Started Nov 2021; still recruiting 5 years later.
Phase
Phase 2
Study type
Interventional
Enrollment
25
Allocation
Randomized
Ages
18 Years to 75 Years
Sex
All
01

Study summary

This research study is evaluating the effectiveness of escalating doses of Amitriptyline and Duloxetine in reducing cough frequency in patients with interstitial lung disease (ILD)-related cough.

Read the detailed description

This is a randomized, double-blind, placebo-controlled, parallel-arm, dose escalation study of Duloxetine \& Amitriptyline in subjects with interstitial lung disease-related chronic cough. Subjects will be screened during a period of up to 2 week and will undergo screening/ baseline cough monitoring. A total of 25 subjects who meet entry criteria will be randomly assigned in a 1: 1: 1: 1: 1 ratio to one of five treatment arms using stratified randomization in blocks of 5. Each arm will have two successive 4-week treatment periods (Blinded Period 1 \& 2). After this, patients will be unblinded and receive routine clinical care. During the unblinded (routine clinical care) follow up phase; subjects will be initially offered the option of continuing amitriptyline or duloxetine based on their initial randomization arm. Subjects could also choose an alternative chronic cough therapy (e.g. pregabalin, gabapentin, 1% tetracaine lollipop or nebulized lidocaine or combination therapy).

Subjects in treatment arm 5, who received placebo during the 8 weeks blinded period will have a discussion regarding all available cough therapies. Patients will be offered the flexibility of therapy options during the unblinded follow up as they would during routine clinical care. Participation in the unblinded follow-up period will be optional.

Treatment Arm 1:

Blinded Period 1 (1st 4 weeks): 30mg of Duloxetine Blinded Period 2 (2nd 4 weeks): 30mg of Duloxetine \& 30mg of Placebo Unblinded (routine clinical care) follow up period: (up to 52 weeks): Subjects will be offered routine clinical care management for their chronic cough

Treatment Arm 2:

Blinded Period 1 (1st 4 weeks): 30mg of Duloxetine Blinded Period 2 (2nd 4 weeks): 60mg of Duloxetine (2 pills of 30mg each) Unblinded (routine clinical care) follow up period: (up to 52 weeks): Subjects will be offered routine clinical care management for their chronic cough

Treatment Arm 3:

Blinded Period 1 (1st 4 weeks): 25mg of Amitriptyline Blinded Period 2 (2nd 4 weeks): 25mg of Amitriptyline + 25mg of Placebo Unblinded (routine clinical care) follow up period: (up to 52 weeks): Subjects will be offered routine clinical care management for their chronic cough

Treatment Arm 4:

Blinded Period 1 (1st 4 weeks): 25mg of Amitriptyline Blinded Period 2 (2nd 4 weeks): 50mg of Amitriptyline (2 pills of 25mg each) Unblinded (routine clinical care) follow up period: (up to 52 weeks): Subjects will be offered routine clinical care management for their chronic cough

Treatment Arm 5:

Blinded Period 1 (1st 4 weeks): 30mg of Placebo Blinded Period 2 (2nd 4 weeks): 60mg of Placebo (2 pills of 30mg each) Unblinded (routine clinical care) follow up period: (up to 52 weeks): Subjects will be offered routine clinical care management for their chronic cough

02

Conditions studied

  • Interstitial Lung Disease

Keywords

  • ILD
  • cough
  • chronic cough
  • refractory
  • antitussives
  • IPF
  • fibrosis
  • UIP
  • NSIP
  • pulmonary fibrosis
03

In context

Lung Diseases, Interstitial

680 studies on the registry are indexed under Lung Diseases, Interstitial; 246 are open to participants now.

This study's planned enrollment of 25 is below the median of 60 across 384 interventional studies indexed under Lung Diseases, Interstitial.

Browse Lung Diseases, Interstitial studies →

Lead sponsor

Mayo Clinic is the lead sponsor of 3,269 studies on the registry; 672 are open to participants now.

Of its 452 completed or terminated interventional studies of FDA-regulated products, 321 (71%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 75 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Have a diagnosis of interstitial lung disease according to the American Thoracic Society Guidelines
  • Have a chronic cough for at least 3 months prior to the screening visit
  • Patients should be on a stable dose of ILD-directed therapies for 3 months prior to enrollment and will be allowed to continue their ILD-directed therapies. These include -but are not limited to- , agents such as azathioprine and mycophenolate, as well as antifibrotic medications including nintedanib and pirfenidone. Additional corticosteroids and adjustment of ILD-directed therapy doses is permitted if deemed appropriate by the treating physician
  • Have a score of ≥ 40mm on the Cough Severity VAS at Screening.
  • Women of must agree to use 2 forms of acceptable and make no donation of eggs from Screening through the end of the 8-week study period. Acceptable birth control methods include established use of oral, injected, or implanted hormonal methods of contraception; intrauterine device (IUD) or intrauterine system (IUS); tubal ligation; or male sterilization. Double-barrier method (diaphragm for female subject and condom for male partner with spermicidal) satisfies the requirement for 2 forms of acceptable birth control. When concordant with the preferred lifestyle of the subject, true and complete abstinence (not periodic abstinence) is acceptable.
  • Male subjects and their partners of child-bearing potential must use 2 methods of acceptable birth control, 1 of which must be a barrier method, and make no donation of sperm from Screening until 3 months after the last dose of study drug at the end of 8 weeks.
  • Have provided written .
  • Are willing and able to comply with all aspects of the protocol.

Exclusion criteria

Exclusion Criteria

  • Current smoker (cigarettes, e-cigarettes or marijuana) or former smokers who have smoked within the past 12 months.
  • Former smokers with > 20 pack-year history of smoking
  • Ongoing treatment with an ACE-inhibitor that is considered as the potential cause of a subject's cough or requiring treatment with an ACE-inhibitor during the study or within 12 weeks prior to the Screening/Baseline Visit (Day -14 to Day 0).
  • History of upper or lower respiratory tract infection or recent significant change in pulmonary status within 4 weeks of the Screening/Baseline Visit (Day -14 to Day 0)
  • History of opioid use specifically prescribed for chronic cough within 2 weeks of the Screening/Baseline Visit (Day -14 to Day 0). Use of opioids for other indications (for example, to treat pain) is permitted.
  • History of baclofen use specifically prescribed for chronic cough within 2 weeks of the Screening/Baseline Visit (Day -14 to Day 0). Use of baclofen for other indications (for example, to treat spasticity) is permitted.
  • Presence of an untreated or undertreated cause (other than ILD) for the patient's chronic cough (as determined by the treating/referring physician per ACCP guidelines). e.g. uncontrolled asthma, GERD or post-nasal drainage that could potentially explain the patient's chronic cough.
  • Requiring concomitant therapy with prohibited medications (listed below).
  • Treatment with any pharmaceutical or biological therapy (excluding coronavirus disease of 2019 (COVID) vaccination and COVID related monoclonal antibody therapy)
  • Participation in another clinical trial that does not allow co-enrollment within 4 weeks prior to the Screening/Baseline Visit (Day -14 to Day 0)
  • Total , (ALT) or aspartate aminotransferase (AST) > 3x the (ULN) during screening.
  • Serum creatinine \< 30 mL/min, hemodialysis or peritoneal dialysis
  • Advanced liver disease as defined by the presence of cirrhosis and/or signs of portal hypertension
  • History of previous or intolerance to Duloxetine \& Amitriptyline (patients who have previously been on either amitriptyline or duloxetine for chronic cough or other reasons and have tolerated the medication will be offered participation regardless of previous response to therapy).
  • Currently pregnant or breastfeeding female subject.
  • Presence of any medical condition or disability that the investigators believe could interfere with the assessment of safety or efficacy in this trial or compromise the safety of the subject.
  • Planned or anticipated major surgical procedure or other activity that would interfere with the subject's ability to comply with protocol-mandated assessments (e.g., extended travel) during the subject's participation in the study.
  • Currently taking either another SSRI, SNRI or MAO inhibitor which the patient cannot safely discontinue at least 2 weeks prior to the screening period.

Therapies that are prohibited during the 8-week blinded phase of the study:

The following therapies are prohibited from 2 week prior to the Screening/Baseline Visit (Day -14 to Day 0) through the end of the 8-week blinded treatment period.

  • Opioids (of any kind including tramadol \& codeine) specifically prescribed for treatment of cough
  • Dextromethorphan
  • Guaifenesin
  • Chlorpheniramine
  • Benzonatate
  • Trazodone
  • Pregabalin or gabapentin prescribed for chronic cough
  • 1% tetracaine lollipops prescribed for chronic cough
  • 4% nebulized lidocaine solution prescribed for chronic cough
  • Any SSRI (selective serotonin reuptake inhibitor) e.g. bupropion, citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine.
  • Any SNRI (serotonin-norepinephrine reuptake inhibitor) e.g. venlafaxine, desvenlafaxine, milnacipran, levomilnacipran
  • Any Tricyclic antidepressant e.g. doxepin, clomipramine, nortriptyline, imipramine, protriptyline, amoxapine, trimipramine
  • Any MAO (Monoamine oxidase) inhibitor. e.g. phenelzine, selegiline, isocarboxacid or tranylcypromine
  • Patients who were previously prescribed either amitriptyline or duloxetine for chronic cough will be eligible for the study as long as they had discontinued the medication at least 12 weeks prior to the Screening/Baseline Visit (Day -14 to Day 0).

The following therapies are prohibited from 4 week prior to the Screening/Baseline Visit (Day -14 to Day 0) through the end of the 8-week blinded treatment period.

  • Investigational biologic or pharmaceutical therapies (excluding COVID vaccination and COVID related monoclonal antibody therapy)

The following therapies are prohibited from 12 week prior to the Screening/Baseline Visit (Day -14 to Day 0) through the end of the 8-week blinded treatment period.

  • Treatment with an ACE-inhibitor
Terms in these criteria, in plain language(10)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Bilirubin

A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.

Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
25 participants (estimated)

Study arms

  • Experimental
    Duloxetine and Placebo

    Subjects will receive 30mg of Duloxetine for blinded period 1 (first 4 week treatment period) and 30mg of Duloxetine plus 30mg Placebo for blinded period 2 (additional 4 weeks treatment period). After this, subjects will be unblinded and receive routine clinical care for follow up phase (up to 52 weeks).

    Drug: Duloxetine 30 MG · Drug: Placebo 30 MG

  • Experimental
    Duloxetine dose escalation

    Subjects will receive 30mg of Duloxetine for blinded period 1 (first 4 week treatment period) and 60mg of Duloxetine for blinded period 2 (additional 4 weeks treatment period). After this, subjects will be unblinded and receive routine clinical care for follow up phase (up to 52 weeks).

    Drug: Duloxetine 30 MG · Drug: Duloxetine 60 MG

  • Experimental
    Amitriptyline and Placebo

    Subjects will receive 25mg of Amitriptyline for blinded period 1 (first 4 week treatment period) and 25mg of Amitriptyline plus 30mg Placebo for blinded period 2 (additional 4 weeks treatment period). After this, subjects will be unblinded and receive routine clinical care for follow up phase (up to 52 weeks).

    Drug: Amitriptyline 25 MG · Drug: Placebo 30 MG

  • Experimental
    Amitriptyline dose escalation

    Subjects will receive 25mg of Amitriptyline for blinded period 1 (first 4 week treatment period) and 50mg of Amitriptyline for blinded period 2 (additional 4 weeks treatment period). After this, subjects will be unblinded and receive routine clinical care for follow up phase (up to 52 weeks).

    Drug: Amitriptyline 25 MG · Drug: Amitriptyline 50 MG

  • Placebo comparator
    Placebo

    Subjects will receive 30mg of Placebo for blinded period 1 (first 4 week treatment period) and 60mg of Placebo for blinded period 2 (additional 4 weeks treatment period). After this, subjects will be unblinded and receive routine clinical care for follow up phase (up to 52 weeks).

    Drug: Placebo 30 MG · Drug: Placebo 60 MG

Interventions

06

What researchers measure

Primary outcomes

  1. Change in awake objective cough frequency (at 4 & 8 weeks)

    The primary objective is to evaluate awake cough frequency at 4 and 8 weeks using the Leicester Cough Monitor. The acoustic cough monitor recordings will be analyzed using the Leicester Cough Monitor program V2.3-MB. This will also be performed at months 4, 6, 9 \& 12 for subjects who choose to continue with the optional unblinded continuation of the study after the initial 8 weeks.

    Time frame: 4 weeks, 8 weeks

Secondary outcomes

  1. Change in 24-Hour cough frequency

    This will also be evaluated using using the Leicester Cough Monitor and recordings will be analyzed using the Leicester Cough Monitor program V2.3-MB. All recordings will be kept confidential on a secure encrypted device. This will also be performed at months 4, 6, 9 \& 12 for subjects who choose to continue with the optional unblinded continuation of the study after the initial 8 weeks.

    Time frame: 4 weeks, 8 weeks

  2. Change in Cough Severity Diary score

    Measured using self-reported Cough Severity Diary that patients will fill at baseline and on daily basis. Change in self-reported Cough Severity Diary score at 4 and 8 weeks will be evaluated. Patients will be asked a series of 6 questions including and will provide an answer using a 5-point Likert scale (never, rarely, sometimes, often, constantly). The following questions will be evaluated: In the past 24 hours, how often did you cough? In the past 24 hours, how often did you experience coughing fits? In the past 24 hours, how severe was your cough? In the past 24 hours, how often did you have an urge to cough? In the past 24 hours, how often could you control your cough? In the past 24 hours, how severe was your pain from coughing? This will also be performed at months 4, 6, 9 \& 12 for subjects who choose to continue with the optional unblinded continuation of the study after the initial 8 weeks

    Time frame: 4 weeks, 8 weeks

  3. Change from Baseline in Leicester Cough Questionnaire (LCQ-acute) individual domain and total scores

    The Leicester Cough Questionnaire (Acute) is a validated tool for the assessment of chronic cough. It evaluates physical, psychological and social domains and how they are impacted by chronic cough. The physical domain consists of 8 questions, the psychological domain consists of 7 questions, and the social domain consists of 4 questions. The domain score will be calculated as the total score from questions in the domain divided by the number of items in the domain (range 1-7). The total score is the sum of individual domain scores and ranges from 3-21. The individual domain as well as the total score will be reported on weeks 4 \& 8. This will also be performed at months 4, 6, 9 \& 12 for subjects who choose to continue with the optional unblinded continuation of the study after the initial 8 weeks.

    Time frame: 4 weeks, 8 weeks

  4. Change in Cough Severity Visual Analogue Scale (VAS)

    Scored on a 100 mm visual analogue scale at Screening/ Baseline visit (Day -14 to Day 0), and on Days 28, and 56. This will also be performed at months 4, 6, 9 \& 12 for subjects who choose to continue with the optional unblinded continuation of the study after the initial 8 weeks.

    Time frame: 4 weeks, 8 weeks

07

Study locations

1 of 1 sites recruiting
  • Mayo Clinic in Rochester
    Rochester, Minnesota 55905, United States
    Recruiting
    • Sue Ann Donlinger · ContactDonlinger.SueAnn@mayo.edu · 507-284-9259
    • · ContactMACS@mayo.edu
    • Vivek N Iyer, M.D, M.P.H · Principal investigator
    • Sumera R Ahmad, M.D. · Sub investigator
    • Sumedh S Hoskote, M.D. · Sub investigator
    • Ashley M Egan, M.D. · Sub investigator
08

References and documents

Individual participant data

Plan to share: No

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Nov 2021 (actual). Primary completion is estimated for Oct 2026, 59 months after the start.

Of 53 phase 2 interventional studies under Lung Diseases, Interstitial, half reached primary completion within 48 months of starting (the median), counting those still running; a quarter within 30 and three quarters within 71. This study's planned 59 months is above that.

How these figures are worked out, and which studies are left out of them.

Registered
Nov 3, 2021
First posted
Nov 16, 2021
StartActual
Nov 1, 2021
Primary completionEst.
Oct 2026
CompletionEst.
Oct 2026
Last update
Jan 21, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Jan 21, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05120934
Lead sponsor
Mayo Clinic
Responsible party
Vivek N Iyer (Principal Investigator, Mayo Clinic) — Principal investigator
First posted
Nov 16, 2021
Start date
Nov 1, 2021
Primary completion
Oct 2026 (estimated)
Completion
Oct 2026 (estimated)
Last update
Jan 21, 2026

Study contacts

Vivek N Iyer, MD
principal investigator · Mayo Clinic

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

No contact was published for this record. The registry link below has the sponsor’s details.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Studies of the drugs tested here: Amitriptyline · Duloxetine

Start the discussion