This is phase 1, open-label, randomized clinical protocol to develop a human challenge model using the licensed and available BCG VACCINE USP (TICE® strain) with and without antibacterial Isoniazid (INH). It will involve 10 participants who will be screened and consented, given an intradermal injection of BCG; five of these participants will receive oral INH for 3 days. Participants will undergo physical exams, clinical evaluations, blood draws, urine collections, skin biopsies, and pregnancy tests. This study will measure the rate of replication by utilizing qPCR and in vitro culture, systemic innate and adaptive immune responses, including humoral and cellular assay analyses and the evaluation and PPD/IGRA status.
The purpose of the study is to develop a BCG challenge model for use in short term Phase I human trials capable of assessing the ability of TB drugs and/or vaccine-induced immune responses to impact in vivo mycobacterial replication as a method of assessing antimycobacterial agents and/or protective immunity elicited by vaccines or host-directed therapy. The trial will illuminate the nature of local and systemic immune responses to BCG and treatment response, as well as demonstrate our local capacity for newer, more innovative study designs.