In asymptomatic SARS-CoV-2 people, Kabasura Kudineer (KSK, a polyherbal Siddha formulation) was found to considerably decrease the load of virus (as estimated by cyclic threshold (CT) value of reverse-transcription polymerase chain reaction [RT-PCR]) in comparison with zinc and vitamin C supplementation. No adverse effects were recorded. S. Natarajan et al. undertook a randomized controlled trial to examine the efficacy of KSK to reduce SARS-CoV-2 load and prevent the advancement of disease in asymptomatic coronavirus cases.

This open-label, prospective, single-center, exploratory study enrolled RT-PCR-confirmed coronavirus people without co-morbidities and clinical symptoms. Overall, 60 participants (age 18-55 years of age) were randomly allocated to the KSK group (30 participants received 60 mL KSK twice daily for seven days) or the standard of care group (30 participants received seven days supplementation of  100 mg zinc every evening and  60,000 IU vitamin C every morning).

Decrease in the viral load, alterations in the immunological markers including interferon-gamma, interleukins (IL-6, IL-10, IL-2), and tumor necrosis factor-alpha, and prevention of advancement of asymptomatic to the symptomatic state were the major endpoints. The secondary endpoints were Siddha clinical assessment and the incidence of adverse effects. For statistical evaluations, paired t-test was utilized.

A substantial decrease in viral load in terms of the CT value (RNA-dependent RNA polymerase 95% CI = 1.89 to 5.74) was witnessed on the 7th day in the KSK group when compared to the control group.  None advanced to the symptomatic state. In terms of biochemical parameters, no profound differences were noted.

In both KSK group and standard of care group, no alterations in Siddha-based clinical examination and adverse events were noted during the study period. Larger, robust multi-centric clinical trials might help in strengthening the current findings, concluded the study authors.