Evaluating the Early Bactericidal Activity, Safety and Tolerability of Nebulised RESP301 in Adults With Tuberculosis

A Phase 2 Study to Evaluate the Early Bactericidal Activity, Safety and Tolerability of Nebulised RESP301 in Adults With Newly Diagnosed, Rifampicin Susceptible Pulmonary Tuberculosis

A Phase 2, Single-Centre, Open-Label, Parallel Control Arm, Randomised Clinical Study to Evaluate the Early Bactericidal Activity (EBA), Safety and Tolerability of Nebulised RESP301 in Adults with Newly Diagnosed, Rifampicin Susceptible Pulmonary Tuberculosis

A total of approximately 15 participants will be recruited per treatment arm (total of approximately 75 participants in the study). Control arm participants will be split across sequential stages stages 1 and 2, with no stratification.

Stage 1: To determine the EBA of

• Treatment Arm 1 (Active; n = 15) - inhaled RESP301 6 ml dosed via nebulisation administered three times daily over 14 days
• Treatment Arm 2 (Control; n= 5) - HRZE taken orally once daily

On completion of Stage 1, recruitment will be paused and an interim analysis performed to determine whether the study should proceed to Stage 2.

Stage 2: To determine the EBA of

• Treatment Arm 2 (Control; n= 10) - HRZE taken orally once daily
• Treatment Arm 3 (Active; n = 15) - inhaled RESP301 6 ml dosed via nebulisation administered once daily over 14 days
• Treatment Arm 4 (Active; n = 15) - inhaled RESP301 6 ml dosed via nebulisation administered twice daily over 14 days
• Treatment Arm 5 (Active; n = 15) - inhaled RESP301 6 ml dosed via nebulisation administered three times daily in combination with HRZE taken orally once daily over 14 days

Inclusion Criteria:

• Provide written, informed consent prior to all study-related procedures and agree to undergo all study procedures
• Body weight (in light clothing and with no shoes) between 40 and 90 kg, inclusive
• Newly diagnosed pulmonary TB
• Rifampicin susceptible pulmonary TB as determined by molecular testing
• Ability to produce an adequate volume of sputum as estimated from a pre-treatment overnight sputum collection sample (estimated 10 ml or more)
• Spirometry performed during screening with a FEV1 of ≥ 40%
• Be of non-childbearing potential or willing to use effective methods of contraception

Exclusion Criteria:

• HIV positive AND CD4 < 350 cells/mm3 OR are receiving antiviral therapy (ART)
• Methaemoglobin saturation (SpMet) >3%
• Female participant who is pregnant or breast-feeding
• Participants planning to conceive a child within the anticipated period of study participation and for at least 90 days after the last dose of IMP in the study
• Participation in other clinical studies with investigational agents within 8 weeks prior to screening
• Treatment received for this episode of TB with any drug active against M.tb
• 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.
• Treatment with nitric oxide and other nitric oxide donor agents, phosphodiesterase inhibitors and lung surfactant drugs, within 30 days prior to screening