The Australian firm donated 92,000 individual doses of two different products: one containing a combination of zinc 40mg, vitamin C 250mg, vitamin E 200IU, and copper 1mg, and a second product containing solely vitamin C 250mg.
The randomised trial was conducted by the National University Hospital in Singapore among the City State’s migrant workers.
Neither Blackmores, nor its research arm the Blackmores Institute, had any involvement in the study design, conduct, analysis or reporting of the trial.
According to the peer-reviewed study, a sub-group analysis of workers which contracted COVID-19 found those taking the zinc combination twice a day experienced a significant increase in spike and neutralising antibody production, compared to the other groups.
In particular, the extent of increase in serum zinc was linked to increases in spike antibodies.
Writing in the journal Clinical and Translational Medicine, researchers said that findings from the study, which involved 4257 men, highlighted suboptimal production of neutralising antibodies in more than 50% of individuals following an asymptomatic infection.
However, compared with other interventions, those who received zinc and vitamin C were found to subsequently mount a greater antibody response.
“Among individuals who were initially seronegative to neutralising antibodies at study entry, conversion
to positivity was approximately four times higher among zinc-treated men compared with those who received other interventions. By activating innate and adaptive B and T cellular responses, the immune system produces binding antibodies especially against the nucleocapsid and spike proteins of the SARS-CoV-2 virus, and neutralising antibodies to aid immunity,” they added.
The authors suggested that future studies should examine the possible prevention benefits of enhanced immune function due to zinc combinations and whether it could also improve responses to vaccines among immunocompromised people.
Professor Lesley Braun, director of the Blackmores Institute, said: “Blackmores was honoured to be invited to support one of the largest nutritional intervention studies conducted on this major public health issue.
“It helps us better understand the role of supplementation in viral diseases and the body’s response, not just for now, but also for the future.
“As an industry leader, we are committed to being part of the global response and building evidence as a means of discovering supportive treatments which are safe and readily available.
“It is fundamental to our work and speaks to our guiding principle at the Blackmores Institute of ‘sharing knowledge, changing lives’.”
The firm says it has a long history of supporting communities when they are in need.
Professor Braun added: “Recently we donated supplements directly to the victims of flooding in Northern NSW as part of a broader community response. This was based on research conducted after the Christchurch earthquakes in New Zealand which demonstrated vitamin B complex supports a healthy stress response.”