Nebulised RESP30TB for newly diagnosed pulmonary tuberculosis

A Phase 2 Trial to Evaluate the Safety and Tolerability and Early Bactericidal Activity of Nebulised RESP30TB in Adults With Newly Diagnosed, Rifampicin Susceptible Pulmonary Tuberculosis

This will test whether inhaled RESP30TB is safe, tolerable, and can quickly kill TB bacteria in adults with newly diagnosed rifampicin‑susceptible pulmonary tuberculosis.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 24 (estimated)
• Ages: 18 Years to 65 Years
• Sex: All
• Sponsor: Thirty Respiratory Limited (Industry-sponsored)
• Locations: 1 site (Cape Town, Bellville)
• Trial ID: NCT07073638 on ClinicalTrials.gov

What this trial studies

This is an open‑label, single‑arm Phase 2 study conducted at one center in two sequential stages enrolling a total of 24 adults. Participants with newly diagnosed, rifampicin‑susceptible pulmonary TB will receive nebulised RESP30TB alongside standard HRZE therapy and undergo serial sputum and safety assessments. Early bactericidal activity will be measured from sputum samples, and safety evaluations include spirometry and methemoglobin monitoring. The design requires ability to produce sputum and excludes patients with significant immunosuppression, pregnancy, or severe baseline lung impairment.

Who should consider this trial

Good fit: Adults with newly diagnosed, rifampicin‑susceptible pulmonary tuberculosis who can produce adequate sputum, weigh 40–90 kg, have FEV1 ≥ 40%, and are not pregnant or severely immunosuppressed are the intended candidates.

Not a fit: Patients with rifampicin‑resistant TB, pregnant or breastfeeding people, those with baseline methemoglobin >3%, severe lung impairment, or HIV with low CD4 or on ART are unlikely to benefit or are excluded.

Why it matters

Potential benefit: If successful, inhaled RESP30TB could reduce lung bacterial load more rapidly and potentially improve or shorten TB treatment for eligible patients.

How similar studies have performed: Aerosolized anti‑TB approaches have been explored in early‑phase studies with mixed results and RESP30TB represents a novel formulation with limited prior human efficacy data.

Eligibility criteria

Inclusion Criteria:

1. Provide written, informed consent prior to all trial-related procedures and agree to undergo all trial procedures.
2. Body weight (in light clothing and with no shoes) between 40 and 90 kg, inclusive.
3. Newly diagnosed pulmonary TB.
4. Rifampicin susceptible pulmonary TB as determined by molecular testing.
5. Ability to produce an adequate volume of sputum as estimated from a pre-treatment overnight sputum collection sample (estimated 10 mL or more).
6. Spirometry performed during screening with a Forced Expiration Volume in the first second (FEV1) of ≥ 40%.
7. Be of non-childbearing potential or willing to use effective methods of contraception, as defined in section 4.3.4.

Exclusion Criteria:

1. HIV positive AND CD4 \< 350 cells/mm3 OR are receiving antiviral therapy (ART)
2. Baseline Methaemoglobin saturation (SpMet) \>3%.
3. Female patients who is pregnant or breast-feeding.
4. Patients planning to conceive a child within the anticipated period of trial participation and for at least 90 days after the last dose of IMP in the trial.
5. Participation in other clinical studies with investigational agents within 8 weeks prior to screening.
6. Treatment received for this episode of TB with any drug active against M.tb
7. Treatment with immunosuppressive medications such as TNF-alpha inhibitors within 2 weeks prior to screening, or systemic corticosteroids for more than 7 days within 2 weeks prior to screening.
8. Treatment with NO and other NO donor agents, phosphodiesterase inhibitors and lung surfactant drugs, within 30 days prior to screening.

Where this trial is running

Cape Town, Bellville

• TASK Clinical Research Centre — Cape Town, Bellville, South Africa (Recruiting)

Conditions Pulmonary Tuberculoses