How the immune protein IDO weakens defenses in tuberculosis and whether blocking it helps

Myeloid and lymphoid immunity-specific mechanisms of IDO mediated immunosuppression and its reversal, during TB

['FUNDING_R01'] · TEXAS BIOMEDICAL RESEARCH INSTITUTE · NIH-11295984

This work looks at whether blocking a protein called IDO can help the immune system fight tuberculosis in people and in animal models, including TB/HIV co-infection.

Quick facts

Phase['FUNDING_R01']
Study typeNih_funding
SexAll
SponsorTEXAS BIOMEDICAL RESEARCH INSTITUTE (nih funded)
Locations1 site (SAN ANTONIO, UNITED STATES)
Trial IDNIH-11295984 on ClinicalTrials.gov

What this research studies

Researchers use a macaque model that mimics natural TB and TB/HIV co-infection alongside studies of human lung TB granulomas to understand how IDO suppresses immune cells. They block IDO enzymatic activity with an FDA-approved compound that has already shown benefit in macaques and examine how granulomas, T cell location, and bacterial killing change. The team also studies how IDO blockade works together with standard anti-TB drugs and in the setting of HIV co-infection. Outcomes measured include clinical signs, survival, tissue changes in granulomas, and immune and metabolic signaling pathways.

Who could benefit from this research

Good fit: People with active pulmonary tuberculosis, including those with HIV co-infection or drug-resistant TB, would be the most likely candidates for related clinical testing.

Not a fit: People with latent TB, TB limited to non-lung sites, or those who cannot receive immune-modulating treatments may not benefit from this approach.

Why it matters

Potential benefit: If successful, this approach could become an add-on therapy that helps antibiotics work better, improves immune control of TB, and reduces disease and death.

How similar studies have performed: Prior work in macaques and analyses of human TB granulomas showed that blocking IDO reshaped granulomas, increased T cell activity, and improved outcomes, so this approach has encouraging preclinical support.

Where this research is happening

SAN ANTONIO, UNITED STATES

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.

View on NIH RePORTER →

Conditions: Acquired Immune Deficiency Syndrome Virus, Acquired Immunodeficiency Syndrome Virus

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.