We reported last year on how Canadian academics had uncovered promising signs that CBD extracts from cannabis could help fight Covid-19 from by preventing it hijacking the body’s cells.

Now the same team have published follow-up research suggesting that some strains of cannabis could help tame the excessive immune-system response to coronavirus complications – known as a ‘cytokine storm’ – which hastens the deaths of some patients.

As with the earlier study, the conclusions – as the researchers acknowledge – come with caveats. The study is still in the process of being peer-reviewed, and the team emphasise that positive results were only achieved from certain types of cannabis.

That means reaching for your vaporizer or bottle of CBD oil should by no means be seen as a panacea in the event you get a positive Covid test. Still, the study presents heartening avenues for exploration as the world continues to battle the pandemic.

Storm inside

Thankfully the death rate of people who become seriously ill with coronavirus has declined since last year as treatments have improved and medical professionals have begun to get its measure.

But recent studies suggest that between five and 10% of those hospitalised are still likely to die.

In some patients the pneumonia the virus can trigger worsens dramatically when the immune system effectively becomes turbocharged and begins attacking the body – the cytokine storm.

This leads to acute respiratory distress syndrome (ARDS), which frequently brings about the death and for survivors can mean irreparable scarring – or fibrosis – of the lungs.

Getting the right strain

With the potential of cannabis in tackling other inflammatory diseases already being explored, the Canadian research team – which has developed more than 1,500 strains of the plant – hypothesized that some of these could be of use in severe cases of Covid.

“When we started reading up in the literature on what drives ARDS, it’s very clear that it’s driven by the same molecules that are implicated in a lot of autoinflammatory and autoimmune diseases,” said Dr Olga Kovalchuk, one of the study leads at the University of Lethbridge.

The research identified three new strains of cannabis that resulted in a “profound and concerted down-regulation of… cytokines and pathways related to inflammation and fibrosis”.

Importantly it also found that other varieties appeared useless – and in one case could make matters worse.

Clearly, this highlights the need for full-scale clinical trials to assess the extent to which different cannabis or CBD products have the potential to mitigate Covid-pneumonia.

The Canadian academics are now searching for partners with whom they can undertake these next steps. We’ll await updates with interest and report back when we have more information.