Proposing Bromo-Epi-Androsterone for Host-Directed Therapy Against Tuberculosis

Bromoepiandrosterone (BEA), a synthetic analog of the adrenal steroid DHEA, holds promise as a host-directed therapy for both active and latent tuberculosis (TB). Unlike DHEA, BEA lacks hormonal side effects yet retains potent immunomodulatory activity. It promotes a Th1-skewed immune response by enhancing interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), critical cytokines for macrophage activation and intracellular control of Mycobacterium tuberculosis (Mtb), while suppressing Th2 cytokines such as IL-4. BEA also inhibits 11β-hydroxysteroid dehydrogenase-1, lowering intracellular cortisol levels and reversing the local immunosuppression commonly seen in TB. These features enable BEA to restore immune competency in TB-infected tissues. In murine TB models, BEA halted bacterial growth, reduced pulmonary inflammation, and synergized with standard anti-TB drugs to enhance bacterial clearance. Additionally, DHEA and its analogues have demonstrated direct antimycobacterial activity, likely by interfering with Mtb mycolic acid synthesis, a property BEA is believed to share. For latent TB, BEA's ability to sustain Th1-mediated immunity and counteract immune suppression could help maintain latency and prevent reactivation, especially in immunocompromised individuals. By boosting immune surveillance and potentially contributing to bacillary clearance, BEA offers a unique adjunctive approach that complements existing TB treatments without contributing to drug resistance. Its dual function, an immune modulator and antimicrobial agent, supports its use across the TB disease spectrum. These properties position BEA as a novel candidate for host-directed therapy aimed at improving outcomes in both drug-sensitive and drug-resistant TB, as well as therapies aimed at enhancing long-term containment of latent infection.