How immune cells and the lung lining react to Pneumocystis infection

Pneumocystis: Macrophage & Epithelial Activation

['FUNDING_R01'] · MAYO CLINIC ROCHESTER · NIH-11266158

This work looks at whether blocking a protein called CARD9 can reduce harmful lung inflammation in people with Pneumocystis pneumonia, especially those with advanced HIV/AIDS.

Quick facts

Phase['FUNDING_R01']
Study typeNih_funding
SexAll
SponsorMAYO CLINIC ROCHESTER (nih funded)
Locations1 site (ROCHESTER, UNITED STATES)
Trial IDNIH-11266158 on ClinicalTrials.gov

What this research studies

Researchers study how Pneumocystis jirovecii triggers immune reactions in the lungs, focusing on macrophage activation and responses of airway lining cells. They are testing a small-molecule CARD9 inhibitor (BRD5529) shown in lab experiments to lower inflammatory signaling in macrophages exposed to Pneumocystis. Experiments include cell-based studies and preclinical models to see if blocking CARD9 reduces damaging inflammation while allowing the body to clear the infection. The aim is to find alternatives to high-dose steroids that reduce lung injury without causing extra immune suppression.

Who could benefit from this research

Good fit: Ideal candidates would be people diagnosed with Pneumocystis jirovecii pneumonia (PJP), especially those with advanced HIV/AIDS or other severe immunosuppression and those with refractory disease despite standard antibiotics.

Not a fit: People without PJP, those whose lung problems are caused by other diseases, or patients unable to receive experimental therapies due to severe comorbidities are unlikely to benefit directly from this work.

Why it matters

Potential benefit: If successful, this could lead to new treatments that lower lung inflammation and improve outcomes for people with Pneumocystis pneumonia, particularly those with AIDS who do not respond well to antibiotics alone.

How similar studies have performed: Early laboratory work showed that CARD9 blockade with BRD5529 reduces inflammatory signaling in immune cells stimulated with Pneumocystis, but clinical benefit in patients has not yet been demonstrated.

Where this research is happening

ROCHESTER, 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, Acquired Immunodeficiency Syndrome

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.