The immune system is amazingly complex, precise and synchronised to deliver effective responses against most health insults. Likewise, medical challenges need to be faced with a multidisciplinary, coordinated and target-specific approach.

To be successful, a prior and deep understanding of all the underlying driver mechanisms of a given health problem is key, and SARS-CoV-2 infection is no different. To successfully design strategies to combat COVID-19 disease we need to decipher and understand the pathogenesis, immunity and transmission of the virus. Nowadays, key questions remain unanswered: Why do people respond so differently? How long does immunity last? How well will a vaccine work? …

Beyond the cytokine storm and the neutralising antibodies, SARS-CoV-2 triggers a complex group of defence responses. Understanding innate immune recognition, major histocompatibility complex restriction, activation of signalling pathways, intercellular communication, adaptive immunity and immune memory, amongst others, will be necessary to develop effective therapies. To this end, COVID-19-focused scientists and physicians around the world need to openly share all the high-standard information they gather. The ‘Sisifo paradox’ is not an option in this fight.

In the meantime, complementary approaches looking to boost the immune system are interesting alternatives being explored. In this regard, the use of the BCG-vaccine, known to have beneficial off-target effects, is being studied. Triggering trained immunity, or innate immune memory, can in the short term enhance responsiveness of innate immune cells to a second wave of activation.

While working against the clock to assemble all the pieces of this puzzle to design the most effective multimodal treatments, complementary therapies aiming at strengthening our immune system and provide non-specific protection will be important to explore.

In an attempt to re-use existing resources and provide an alternative, HiTT is helping Archivel Farma to explore the use of RUTIÒ, a non-live M. tuberculosis vaccine, for the prevention of COVID-19 in high-risk population. We are collaborating with best-of class entrepreneurs, scientists and clinical professionals to validate the proposal, and be able to serve the population while waiting for an efficient vaccine and trying to prevent the likely mutations of the virus which a vaccine may not be able to cover.