Phase 2b clinical trial of promising TB vaccine candidate MTBVAC has reached full enrollment

IAVI and Biofabri are proud to announce that the Phase 2b clinical trial of tuberculosis (TB) vaccine candidate MTBVAC reached full enrollment on July 16, 2026. This trial, known as IMAGINE (Investigation of MTBVAC toward Accelerating Global Immunization for a Neglected Epidemic), has successfully completed its target of 5,500 participants enrolled across 16 clinical research centers in South Africa, Kenya, and Tanzania. The IMAGINE trial is designed to access safety and efficacy of MTBVAC in the prevention of active TB lung disease in adolescents and adults with latent TB infection. It also incorporated an additional cohort of participants that have never been exposed to TB infection, allowing for more robust data collection.

“Reaching full enrollment of 5,500 participants in the IMAGINE trial is a tremendous milestone and a testament to the dedication of our participants, investigators, and study teams. Tuberculosis continues to be the leading infectious disease killer worldwide and remains a major global cause of chronic lung damage and disability. While we must await the trial results, completing recruitment brings us one step closer to answering one of the most important questions in global health research today: whether MTBVAC can provide improved protection against tuberculosis. We now eagerly look forward to the next phase of the study and the opportunity to evaluate the promising efficacy of MTBVAC,” said Keertan Dheda, MBBCh, FCP, FCCP, Ph.D., FRCP, professor of respiratory medicine, director of the Centre for Lung Infection and Immunity, head of the Division of Pulmonology in the Department of Medicine at the University of Cape Town, and principal investigator for the IMAGINE trial.  

MTBVAC was developed by the Spanish biopharmaceutical company Biofabri. The IMAGINE trial is sponsored by IAVI and funded by Coefficient Giving, the Gates Foundation, the German Federal Ministry of Research, Technology and Space (BMFTR) through the KfW Development Bank, Wellcome, and Global Health EDCTP3 as part of the MTBVAC AVANTE consortium. The first participant was enrolled in February 2025, marking the start of this large-scale safety and efficacy trial. Results from the preceding Phase 1b/2a A-050 trial were shared in April 2025 and strengthened the program’s rationale with a publication in Lancet Global Health, demonstrating that MTBVAC had a safety profile comparable to the Bacillus Calmette-Guérin (BCG) vaccine at selected doses and induced immune responses in adults that were similar to, or stronger than, those generated by BCG revaccination. 

TB disease caused 1.23 million deaths in 2024 and is widely recognized as the world’s most lethal infectious disease. BCG, the only approved vaccine for TB, was introduced over 100 years ago. It provides important but incomplete protection to young children and does not prevent TB disease in adolescents or adults. A new TB vaccine that is effective across these populations could save millions of lives over time and is a top priority for research and development.   

“This milestone reflects the remarkable effort and collaboration required to conduct a clinical trial of this scale across multiple countries,” said Mark Feinberg, M.D., Ph.D., IAVI CEO and president. “We are grateful to the study participants, investigators, funders, and all partners who are advancing MTBVAC. A new, efficacious, and accessible vaccine against the world’s deadliest infectious disease would be a substantial accomplishment for public health, and IAVI and partners are working to make this a reality.” 

“Completing enrollment in 5,500 adolescents and adults marks one of the most significant milestones in the development of MTBVAC. It brings us closer to understanding the vaccine’s potential to protect the populations most affected by pulmonary tuberculosis and reflects the extraordinary commitment of the volunteers, investigators, and partners whose dedication has made this milestone possible,” said Rolando Pajón, Ph.D., chief medical and scientific officer of Biofabri. 

About MTBVAC 

MTBVAC is a single-dose vaccine delivered via intradermal delivery. It does not require an adjuvant and is well-suited for use in difficult-to-reach locations. MTBVAC was designed by the Spanish researcher Carlos Martin, from the University of Zaragoza, and Brigitte Gicquel, Ph.D., of Institut Pasteur, and was industrially developed and in-licensed by Biofabri (Zendal Group). It is the only live-attenuated TB vaccine candidate derived from M.tb in current trials. This is a notable difference from BCG, the only approved TB vaccine, which is derived from Mycobacterium bovis, the bovine form of tuberculosis. 

About IAVI 

IAVI is a global nonprofit biomedical research organization dedicated to addressing unmet health challenges including HIV, tuberculosis, and a range of emerging infectious diseases. Its mission is to translate scientific discoveries into affordable, globally accessible public health tools. Read more at www.iavi.org. 

About Biofabri 

Biofabri is a biopharmaceutical company founded in 2008 to research, develop and manufacture vaccines for human use. With strong scientific and technical expertise in vaccines and immunotherapy, the company is responsible for the clinical and industrial development of the tuberculosis vaccine candidate MTBVAC, currently in the advanced stages of clinical development. 

Biofabri is part of the Zendal Group, a biopharmaceutical group comprising companies specialized in human and animal health.