On the morning of 28 August 2025, there was a sense of quiet excitement in the clinical research rooms. After months of preparation, our team witnessed a major milestone the first participant in Phase Two of the BCG Controlled Human Infection Model (BCG-CHIM) study was inoculated.

This came just a week after the official start of Phase Two on 21 August 2025, a chapter that represents Malawi’s growing leadership in experimental medicine. Volunteers, clinicians, laboratory staff, and researchers stood together in anticipation, knowing that this single moment would mark the beginning of a journey with global significance.

Tuberculosis (TB) continues to be one of the world’s deadliest infectious diseases, causing over 1.6 million deaths annually, with Malawi among the countries hardest hit. Although the BCG vaccine has been used worldwide for nearly 100 years, it offers limited protection for adults in high-burden settings. To develop better vaccines, researchers need new ways to measure immunity and test candidates effectively.

The BCG-CHIM study is designed to meet that need. By safely re-vaccinating healthy volunteers with BCG under controlled conditions, researchers can closely study immune responses in the skin, blood, and respiratory tract. This innovative model has the potential to accelerate TB vaccine discovery and ensure that new tools are tested in the communities that need them most.

Phase One confirmed that the model is safe and feasible in Malawi. With that foundation, Phase Two is now underway, involving 20 additional participants who are receiving BCG at different doses. This phase sets the stage for using the BCG-CHIM to evaluate future vaccine candidates and even explore potential new TB treatments.

The first inoculation on 28 August is not only a scientific achievement but also a testament to the dedication of the volunteers and the study team. Each step brings us closer to the goal, developing more effective TB vaccines to protect communities in Malawi and around the world.