Retrospective Cohort Observational Study to compare the Effect of Mycobacterium w along with Standard of Care vs Standard of Care alone in critically ill COVID-19 Patients

Background: COVID-19 has created enormous health crisis in India due to limited available treatments. Majority of the physicians use sepsis as a prototype to understand the pathophysiology of COVID-19 as there are similarities. Heat-killed Mycobacterium w (Mw) (Inj. Mw®) is a known immunomodulator, which is approved for the treatment of gram-negative sepsis. This observational study was aimed to evaluate the role of Mw along with standard of care (SOC) in critically ill COVID-19 patients.

Methods: Total 448 patients' data (intervention group: 298 in Mw plus SOC vs 150 in SOC alone) with reverse transcriptase-polymerase chain reaction (RT-PCR) confirmed critically ill COVID-19 patients who were admitted at five tertiary care centers were evaluated. They were observed for changes in laboratory [C-reactive protein (CRP), D-dimer, ferritin, lactate dehydrogenase (LDH), and interleukin-6 (IL-6)] parameters, hospital stay, intensive care unit (ICU) stay, and discharge status after giving 0.3 mL intradermal Mw for 3 consecutive days along with SOC during hospitalization. Standard of care included injectable steroids, remdesivir, and heparin. Data were analyzed using STATA 14.2 (StataCorp., College Station, Texas, USA).

Results: In baseline characteristics, Mw plus SOC arm had more critically ill patients as seen by higher high-resolution computed tomography (HRCT) score, higher lab values [CRP, ferritin, D-dimer, LDH, creatinine, alanine aminotransferase (ALT)], and more oxygen requirement as compared to SOC alone. Mycobacterium w arm had significantly higher mortality rate in ICU and hospital. Both hospital stay and ICU stay were longer in Mw arm. However, subgroup analysis found that early initiation of Mw (<3 days vs >3 days) was associated with significantly lesser odds of mortality and lesser odds of intubation requirement. Early initiation of Mw (<3 days vs >3 days) also resulted in significantly lesser duration of stay in the ICU along with reduction of CRP, D-dimer, and LDH. Moreover, further analysis of early initiation of Mw (<3 days vs control) resulted in significant reduction in lab values (procalcitonin, CRP, ferritin, LDH, and D-dimer).

Conclusion: Mw when added to SOC was found to associate with significantly increased risk of mortality and increased length of hospital stay. However, time since admission to administration of Mw was a significant predictor of in-ICU deaths in multivariate analysis. Early initiation of Mw (<3 days) was observed to be a protective factor against ICU deaths from the multivariate logistic regression model. However, large randomized controlled trials are required to support the same.