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Recruiting Phase 3 NCT05473520

NCT05473520 Doxycycline Host-directed Therapy to Improve Lung Function and Decrease Tissue Destruction in Pulmonary Tuberculosis

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Clinical Trial Summary
NCT ID NCT05473520
Status Recruiting
Phase Phase 3
Sponsor National University Hospital, Singapore
Condition Tuberculosis
Study Type INTERVENTIONAL
Enrollment 150 participants
Start Date 2023-05-24
Primary Completion 2030-01-31

Eligibility & Interventions

Sex All sexes
Min Age 21 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
DoxycyclinePlacebo

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 3 trials are large pivotal studies comparing the treatment to current standard of care or placebo. Your participation directly contributes to the evidence needed for regulatory approval.

This trial targets 150 participants in total. It began in 2023-05-24 with a primary completion date of 2030-01-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Tuberculosis (TB) is a global pandemic that despite successful treatment and bacterial eradication can cause chronic ill health, such as pulmonary impairment after tuberculosis (PIAT) and cardiovascular disease (CVD). A recent Phase 2b double-blind randomised-controlled clinical trial shows that adjunctive doxycycline therapy is safe, accelerates resolution of inflammation, suppresses tissue damaging enzyme activity and decreases pulmonary cavity volume (1). We aim to determine if adjunctive doxycycline can reduce PIAT and improve cardiovascular outcomes in a fully powered Phase III trial of 8 weeks of adjunctive doxycycline alongside standard pulmonary TB (PTB) treatment. The investigators hypothesize that doxycycline inhibits tissue destruction in patients with PTB and thereby leads to improved lung function after treatment. Specific aims 1. To assess improvement in lung function as measured by forced expiratory volume (FEV1) predicted in PTB patients given doxycycline versus placebo. 2. To investigate whether doxycycline will hasten the resolution of pulmonary cavities measured by CT thorax 3. To investigate whether doxycycline can suppress inflammatory markers including matrix metalloproteinases 4. To investigate whether doxycycline can accelerate time to sputum conversion 5. To evaluate the effect of doxycycline on cardiovascular outcomes such as the incidence of acute coronary syndrome (ACS) and pulmonary hypertension 6. To investigate whether doxycycline improves TB drug concentrations in sputum and plasma. 7. To assess the safety profile of doxycycline with concurrent standard anti-tuberculous treatment.

Eligibility Criteria

The recruitment target would be 150 patients, with 75 in each arm Inclusion criteria: Patients should meet all criteria: 1. Aged 21 years and above 2. Patients receiving ≤ 7 days of TB treatment or about to start standard combination TB treatment 3. Confirmed pulmonary TB with positive acid-fast bacilli smear and/or positive nucleic acid amplification test (NAAT) and/or TB culture results 4. CXR demonstrating pulmonary involvement with cavity or cavities 5. Able to provide informed consent Exclusion criteria: 1. HIV co-infection 2. Previous pulmonary TB 3. Severe, pre-existing lung disease such as pulmonary fibrosis, bronchiectasis, COPD and lung cancer 4. Pregnant or breast feeding 5. Allergies to tetracyclines 6. Patients on retinoic acid, neuromuscular blocking agents and pimozide which may increase risk of drug toxicity 7. Autoimmune disease and/or on systemic immunosuppressants 8. Use of any investigational or non-registered drug, vaccine or medical device other than the study drug within 182 days preceding dosing of study drug, or planned use during the study period 9. Enrolment in any other clinical trial involving a systemic drug or intervention involving the lung 10. Evidence of severe depression, schizophrenia or mania 11. ALT \> 3 times upper limit of normal 12. Creatinine \> 2 times upper limit of normal 13. Principal investigator assessment of lack of willingness to participate and comply with all requirements including follow-up of the protocol, or identification of any factor felt to significantly increase the participant's risk of suffering an adverse outcome

Contact & Investigator

Central Contact

Srishti CHHABRA, MBBS BSc MRCP

✉ srishti.chhabra@mohh.com.sg

📞 +65 6908 2222

Principal Investigator

Catherine Ong, MRCP PhD

PRINCIPAL INVESTIGATOR

National University Hospital, Singapore

Frequently Asked Questions

Who can join the NCT05473520 clinical trial?

This trial is open to participants of all sexes, aged 21 Years or older, studying Tuberculosis. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT05473520 trial and what does that mean for participants?

Phase 3 trials are large-scale studies comparing the new treatment to existing standards of care or a placebo. They provide the evidence needed for regulatory approval. This trial targets 150 participants.

Is NCT05473520 currently recruiting?

Yes, NCT05473520 is actively recruiting participants. Contact the research team at srishti.chhabra@mohh.com.sg for enrollment information.

Where is the NCT05473520 trial being conducted?

This trial is being conducted at Kota Kinabalu, Malaysia, Kota Kinabalu, Malaysia, Kota Kinabalu, Malaysia, Kota Kinabalu, Malaysia and 2 additional locations.

Who is sponsoring the NCT05473520 clinical trial?

NCT05473520 is sponsored by National University Hospital, Singapore. The principal investigator is Catherine Ong, MRCP PhD at National University Hospital, Singapore. The trial plans to enroll 150 participants.

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