Mycobacterium indicus pranii (MIP) Vaccine: A Narrative Review of Current Evidence on Selected Clinical Conditions, Challenges, and Future Directions

Mycobacterium indicus pranii (MIP), formerly designated Mycobacterium w (Mw), is an inactivated, heat-killed, non-pathogenic Mycobacterium with well-characterized immunomodulatory properties, originally developed in India. Initially introduced as an adjunct to multidrug therapy (MDT) for leprosy, MIP has since demonstrated significant therapeutic and prophylactic potential across a broad spectrum of infectious and non-infectious conditions, including tuberculosis (TB), COVID-19, leishmaniasis, cutaneous warts, sepsis, and select malignancies. Clinical and observational studies have reported improved clinical outcomes, accelerated bacillary clearance, and sustained immunological benefits across multiple disease contexts. Despite these promising findings, several barriers impede the broader integration of MIP into public health programmes. These include the absence of large-scale, adequately powered efficacy trials; insufficient immunological characterization; limited operational and socio-behavioural feasibility data; poor awareness within the healthcare system; and challenges with long-term patient follow-up, particularly in mobile or migrant populations. Future research directions underscore MIP’s potential as a prophylactic and therapeutic agent against COVID-19, an adjunctive therapy for drug-resistant TB, and an immunotherapeutic candidate in oncology. Addressing existing research gaps through rigorously designed clinical, immunological, and implementation studies will be essential to realizing MIP’s full potential in global health.