Selective β2-AR Antagonism in Asthma

November 26, 2025 updated by: Trio Medicines Ltd.

A Double-blind, Placebo-controlled, Ascending-dose Study to Assess the Safety, Tolerability and Efficacy of TR4, a Selective β2-adrenoceptor (β2-AR) Antagonist, in Patients With Mild-to-moderate Asthma

The objectives are to assess the safety, tolerability and effect on the airways of TR4 in patients with mild-to-moderate asthma. The Phase 1 trial is randomised, double-blind, placebo-controlled, and ascending-dose in design.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

After a run-in period of 2 weeks, 12 eligible patients will be randomised to treatment with either TR4 or placebo. Nine patients will take incremental doses of 2.5, 5, 10 and 20 mg of TR4 capsules, each dose three times daily for 7 days, and then 40 mg three times daily for 21 days, over a total period of 7 weeks. Three patients will take matching placebo capsules in a similar manner.

The number of visits and the types are as follows. There will be a maximum of 10 visits to Hammersmith Medicines Research (HMR) for those subjects who complete the whole study according to the protocol. Visit 1 is an out-patient visit for informed consent and screening. Visit 2 is a short out-patient visit at the start of a 2-week run-in period for those subjects who pass screening. After the run-in period, patients who are still eligible will be given a schedule for 8 further visits (Visits 3-10). Participants will stay on the ward for 2 nights during 5 of those visits (Visits 3-7), and for 1 night during Visit 10. Visits 8 and 9 are short out-patient visits. The study will take each subject ~10 weeks to complete. For purposes of data collection and management the study is divided into one session for screening, a run-in period and 5 treatment periods.

Study Type

Interventional

Enrollment (Actual)

12

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • London
      • London, London, United Kingdom, NW10 7EW
        • Hammersmith Medicines Research

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Men or women
  • Minimum 21 years old
  • History of mild-to-moderate asthma for at least 6 months and controlled by an inhaled SABA, as required
  • Otherwise healthy
  • Ideally have participated in previous asthma studies
  • No corticosteroid for whatever reason within 8 weeks of the start of dosing
  • No other prescription medicine within 28 days (apart from a short acting beta-agonist (SABA) or contraceptives in women)
  • No over-the-counter medicine within 7 days (apart from acetaminophen) before the start of dosing
  • Negative screen for drugs of abuse; forced expiratory volume in 1 second (FEV1) more than or equal to 70% predicted
  • Fractional exhaled nitric oxide (FeNO) more than or equal to 35 ppb
  • 15% fall in FEV1 after inhaled mannitol (PD15)
  • Non-smoker or past smoker (<5 pack years)
  • Substitution of subject's SABA inhaler with an anti-cholinergic inhaler, ipratropium bromide, for use as a reliever or rescue medication during a run-in period and during dosing with TR4 or placebo.

Exclusion Criteria:

  • Positive test for hepatitis B & C or HIV
  • Drug or alcohol abuse
  • Airway infection or asthma exacerbation in the last 4 weeks
  • Current seasonal asthma
  • History of emergency treatment of asthma
  • Loss of more than 400 mL blood, or participation in other clinical trials of unlicensed medicines within the previous 3 months
  • Consumption of grapefruit or herbal remedies within the past 7 days
  • Objection by the subject's general practitioner (GP)
  • Subjects who are sexually active and not using reliable contraception
  • Women who are lactating, pregnant or plan to become pregnant during the study period
  • Positive polymerase chain reaction (PCR) test for SARS-CoV-2 virus
  • Subjects who have not received both doses of a COVID-19 vaccine.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: TR4
After a run-in period of 2 weeks, 9 patients will be randomly assigned to the TR4 treatment arm. These 9 patients will take incremental doses of 2.5, 5, 10, and 20 mg of TR4, each dose three times daily for 7 days, and then 40 mg three times daily for 21 days, over a total period of 7 weeks.
TR4 is a selective beta-2-adrenoceptor antagonist. TR4 will be weighed into opaque capsules and released for individual patients, in accordance with good manufacturing practice (GMP).
Placebo Comparator: Placebo
Three patients will take matching placebo capsules in a similar manner to TR4.
Placebo capsules will contain start in opaque capsules.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mannitol (PD15)
Time Frame: Baseline (day -1) of treatment periods 1 to 5.
The dose of mannitol causing a 15% fall in FEV1
Baseline (day -1) of treatment periods 1 to 5.
Mannitol (PD15)
Time Frame: Day 21 of treatment period 5.
The dose of mannitol causing a 15% fall in FEV1
Day 21 of treatment period 5.
Spirometry (FEV1)
Time Frame: Day 1 of treatment periods 1 to 5.
Lung function test: The forced expiratory volume in 1 second (FEV1).
Day 1 of treatment periods 1 to 5.
Spirometry (FEV1)
Time Frame: Day 2 of treatment periods 1 to 5.
Lung function test: The forced expiratory volume in 1 second (FEV1).
Day 2 of treatment periods 1 to 5.
Spirometry (FEV1)
Time Frame: Day 21 of treatment period 5.
Lung function test: The forced expiratory volume in 1 second (FEV1).
Day 21 of treatment period 5.
Spirometry (FVC)
Time Frame: Day 1 of treatment periods 1 to 5
Lung function test: forced vital capacity (FVC)
Day 1 of treatment periods 1 to 5
Spirometry (FVC)
Time Frame: Day 2 of treatment periods 1 to 5
Lung function test: forced vital capacity (FVC).
Day 2 of treatment periods 1 to 5
Spirometry (FVC)
Time Frame: Day 21 of treatment period 5
Lung function test: forced vital capacity (FVC).
Day 21 of treatment period 5
Spirometry (FEF 25-75)
Time Frame: Day 1 of treatment periods 1 to 5
Lung function test: forced mid-expiratory flow (FEF 25-75) is the mean forced expiratory flow during the middle half of the FVC.
Day 1 of treatment periods 1 to 5
Spirometry (FEF 25-75)
Time Frame: Day 2 of treatment periods 1 to 5
Lung function test: the forced mid-expiratory flow (FEF 25-75) is the mean forced expiratory flow during the middle half of the FVC.
Day 2 of treatment periods 1 to 5
Spirometry (FEF 25-75)
Time Frame: Day 21 of treatment period 5.
Lung function test: forced mid-expiratory flow (FEF 25-75) is the mean forced expiratory flow during the middle half of the FVC
Day 21 of treatment period 5.
Spirometry (FEV1/FVC)
Time Frame: Day 1 of treatment periods 1 to 5.
Lung function test: FEV1 as a percentage of FVC (FEV1/FVC).
Day 1 of treatment periods 1 to 5.
Spirometry (FEV1/FVC)
Time Frame: Day 2 of treatment periods 1 to 5.
Lung function test: FEV1 as a percentage of FVC (FEV1/FVC).
Day 2 of treatment periods 1 to 5.
Spirometry (FEV1/FVC)
Time Frame: Day 21 of treatment period 5.
Lung function test: FEV1 as a percentage of FVC (FEV1/FVC).
Day 21 of treatment period 5.
Impulse oscillometry (IOS) (R5, R5-R20)
Time Frame: Change between baseline (day -1) and day 1 of treatment periods 1 to 5.
Lung function test: A Jaeger impulse oscillometer will be used to obtain measurements according to the investigators standard operating procedure (SOP) and a published algorithm. The following settings will be used for IOS: oscillometric pressure impulses will be superimposed onto the tidal breathing of the subject, for about 30 s, with a pulse sequence of 5 per second and a frequency spectrum between 5 and 35 Hz. Resistance (R) at 5-20 Hz (R5 and R5-R20) during normal tidal breathing will be measured.
Change between baseline (day -1) and day 1 of treatment periods 1 to 5.
IOS (R5, R5-R20)
Time Frame: Day 21 of treatment period 5.
Lung function test: A Jaeger impulse oscillometer will be used to obtain measurements according to the investigators SOP and a published algorithm. The following settings will be used for IOS: oscillometric pressure impulses will be superimposed onto the tidal breathing of the subject, for about 30 s, with a pulse sequence of 5 per second and a frequency spectrum between 5 and 35 Hz. Resistance (R) at 5-20 Hz (R5 and R5-R20) during normal tidal breathing will be measured.
Day 21 of treatment period 5.
IOS (AX)
Time Frame: Change between baseline (day -1) and day 1 of treatment periods 1 to 5.
Lung function test: A Jaeger impulse oscillometer will be used to obtain measurements according to the investigators SOP and a published algorithm. The following settings will be used for IOS: oscillometric pressure impulses will be superimposed onto the tidal breathing of the subject, for about 30 s, with a pulse sequence of 5 per second and a frequency spectrum between 5 and 35 Hz. Reactance (X) at 5-20 Hz (AX) during normal tidal breathing will be measured.
Change between baseline (day -1) and day 1 of treatment periods 1 to 5.
IOS (AX)
Time Frame: Day 21 of treatment period 5.
Lung function test: A Jaeger impulse oscillometer will be used to obtain measurements according to the investigators SOP and a published algorithm. The following settings will be used for IOS: oscillometric pressure impulses will be superimposed onto the tidal breathing of the subject, for about 30 s, with a pulse sequence of 5 per second and a frequency spectrum between 5 and 35 Hz. Reactance (X) at 5-20 Hz (AX) during normal tidal breathing will be measured.
Day 21 of treatment period 5.
Airway nitric oxide (FeNO)
Time Frame: Change between baseline (day -1) and day 1 of treatment periods 1 to 5.
FeNO will be measured using the NIOX Viro handheld electronic device.
Change between baseline (day -1) and day 1 of treatment periods 1 to 5.
Airway nitric oxide (FeNO)
Time Frame: Day 21 of treatment period 5.
FeNO will be measured using the NIOX Viro handheld electronic device.
Day 21 of treatment period 5.
Blood eosinophils
Time Frame: Day -1 of treatment periods 1 to 5.
Blood eosinophils concentration will be used as an inflammatory marker.
Day -1 of treatment periods 1 to 5.
Blood eosinophils
Time Frame: Day 21 of treatment period 5.
Blood eosinophils concentration will be used as an inflammatory marker.
Day 21 of treatment period 5.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Vital signs (safety): Blood pressure
Time Frame: Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Vital signs are assessed to determine safety and tolerability of treatment.
Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Vital signs (safety): Heart rate
Time Frame: Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Vital signs are assessed to determine safety and tolerability of treatment.
Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Vital signs (safety): Respiratory rate
Time Frame: Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Vital signs are assessed to determine safety and tolerability of treatment.
Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Vital signs (safety): Oral temperature
Time Frame: Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Vital signs are assessed to determine safety and tolerability of treatment.
Day 1 and 2 of treatment periods 1 to 5. Day 21 and 22 of treatment periods 3 to 5.
Safety tests of blood and urine
Time Frame: Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
Blood and urine for safety tests will be collected before dosing. Blood will be taken for haematology (2 mL in EDTA), and biochemistry and serology (2 x 3.5 mL).
Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG: Ventricular rate (safety)
Time Frame: Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG will be taken to assess safety and tolerability of treatment. Ventricular rate will be assessed.
Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG: PR interval (safety)
Time Frame: Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG will be taken to assess safety and tolerability of treatment. The PR interval is the time from the onset of the P wave to the start of the QRS complex.
Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG: QRS (safety)
Time Frame: Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG will be taken to assess safety and tolerability of treatment. The QRS complex is the combination of the Q, R and S waves.
Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG: QT interval (safety)
Time Frame: Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
12-lead ECG will be taken to assess safety and tolerability of treatment. Corrected QT interval using the Frederica formula (QTcF).
Day 1 of treatment periods 1 to 5 and day 22 of treatment periods 3 to 5.
ECG telemetry: Ventricular rate (safety)
Time Frame: Day 1 of treatment periods 1 to 5.
The ECG will be monitored continuously from 30 min before until 24h after dosing, using a SpaceLabs system.
Day 1 of treatment periods 1 to 5.
ECG telemetry: PR interval (safety)
Time Frame: Day 1 of treatment periods 1 to 5.
The ECG will be monitored continuously from 30 min before until 24h after dosing, using a SpaceLabs system.
Day 1 of treatment periods 1 to 5.
ECG telemetry: QRS (safety)
Time Frame: Day 1 of treatment periods 1 to 5.
The ECG will be monitored continuously from 30 min before until 24h after dosing, using a SpaceLabs system.
Day 1 of treatment periods 1 to 5.
ECG telemetry: QT interval (safety)
Time Frame: Day 1 of treatment periods 1 to 5.
The ECG will be monitored continuously from 30 min before until 24h after dosing, using a SpaceLabs system.
Day 1 of treatment periods 1 to 5.
Peak expiratory flow rate (PEFR)
Time Frame: Day -1 to 6 for treatment periods 1 and 2. Day -1 to 7 and day 8 and 16 of treatment periods 3 to 5. Day 21 of treatment period 5.
Subjects will be given a PEFR meter. A drop of 20% of a subject's normal PEFR is considered in the normal range.
Day -1 to 6 for treatment periods 1 and 2. Day -1 to 7 and day 8 and 16 of treatment periods 3 to 5. Day 21 of treatment period 5.
FEV1 (safety)
Time Frame: Day -1 of treatment periods 1 to 5.
Forced expiratory volume in 1 second.
Day -1 of treatment periods 1 to 5.
Pulse oximetry
Time Frame: Day 1 and 2 of treatment periods 1 to 5. Day 21 of treatment periods 3 to 5.
Pulse oximetry is a non-invasive method for monitoring the saturation of oxygen in the peripheral blood, which will be measured using the SpaceLabs Patients Care Monitoring System (PCMS) and a standard HMR SOP.
Day 1 and 2 of treatment periods 1 to 5. Day 21 of treatment periods 3 to 5.

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Plasma TR4 and metabolite concentration
Time Frame: Blood samples (4 mL) will be taken on day 1 of treatment periods 1 to 5.
Plasma concentrations of TR4 and metabolites will be listed and summarised by treatment, using descriptive statistics. Individual pharamcokinetic (PK) parameters will be calculated.
Blood samples (4 mL) will be taken on day 1 of treatment periods 1 to 5.
Plasma annexin-A1
Time Frame: Blood samples (5 mL) will be taken on day -1 of treatment periods 1 to 5 and day 21 of treatment period 5.
Annexin-A1 is a global anti-inflammatory protein and its receptor levels are known to be modulated in asthmatics. The investigators are using it as an inflammatory biomarker and will measure concentration in plasma using a validated ELISA method.
Blood samples (5 mL) will be taken on day -1 of treatment periods 1 to 5 and day 21 of treatment period 5.
Lymphocyte beta-2-adrenoceptor density
Time Frame: Blood samples (8 mL) will be taken on day -1 of treatment periods 1 to 5 and day 21 of treatment period 5.
Flow-cytometry assay used to measure cell-surface density of beta-2-adrenoceptor on lymphocyte subtypes.
Blood samples (8 mL) will be taken on day -1 of treatment periods 1 to 5 and day 21 of treatment period 5.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Denisa Wilkes, Hammersmith Medicines Research

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 28, 2018

Primary Completion (Actual)

August 16, 2022

Study Completion (Actual)

August 16, 2022

Study Registration Dates

First Submitted

November 21, 2022

First Submitted That Met QC Criteria

November 26, 2025

First Posted (Estimated)

December 9, 2025

Study Record Updates

Last Update Posted (Estimated)

December 9, 2025

Last Update Submitted That Met QC Criteria

November 26, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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