Molecule Derived From Poisonous Plant Blocks All SARS-CoV-2 Variants in Cell Cultures

A plant-based antiviral treatment for Covid-19, recently discovered by scientists at the University of Nottingham, has been found to be just as effective at treating all variants of the virus SARS-CoV-2, even the highly infectious Delta variant.

The struggle to control the Covid-19 pandemic is made more difficult by the continual emergence of virulent SARS-CoV-2 variants, which are either more infectious, cause more severe infection, or both.

In a new study published in Virulencea group of scientists, led by Professor Kin-Chow Chang from the School of Veterinary Medicine and Science at the University, found that the Delta variant, compared with other recent variants, showed the highest ability to multiply in cells, and was most able to directly spread to neighbouring cells. In co-infections with two different SARS-CoV-2 variants, the Delta variant also boosted the multiplication of its co-infected partners.

The study also showed that a novel natural antiviral drug called thapsigargin (TG), recently discovered by the same group of scientists to block other viruses, including the original SARS-CoV-2, was just as effective at treating all of the newer SARS-CoV-2 variants, including the Delta variant.

In their previous studies* the team showed that the plant-derived antiviral, at small doses, triggers a highly effective broad-spectrum host-centred antiviral innate immune response against three major types of human respiratory viruses, including SARS-CoV-2.

In this latest study, the team set out to find out how well the emergent Alpha, Beta and Delta variants of SARS-CoV-2 are able to multiply in cells relative to each other as single variant infections and in co-infections– where cells are infected with two variants at the same time. The team also wanted to know just how effective TG was at blocking these emergent variants. Notably, all SARS-CoV-2 variants were highly susceptible to TG treatment. A single pre-infection priming dose of TG effectively blocked all single-variant infections and every co-infection at greater than 95% relative to controls. Likewise, TG was effective in inhibiting each variant during active infection.


Drug-free Nasal Spray Prevents SARS-CoV-2 Infection

Auris Medical Holding Ltd. (NASDAQ: EARS), a clinical-stage company dedicated to developing therapeutics that address important unmet medical needs in neurotology, rhinology and allergy and CNS disorders, today announced positive efficacy data from testing AM-301 in vitro. AM-301 is a drug-free nasal spray being developed by the Company’s affiliate Altamira Medica for protection against airborne pathogens and allergens.

AM-301 was tested for its capability to prevent or mitigate SARS-CoV-2 infection of nasal epithelial cells, which are part of the nasal mucosa and the first barrier against continuously inhaled substances such as pathogens and allergens. The experiment was performed over four days on reconstituted human nasal epithelia, which are frequently used to study the effects of human respiratory viruses. In saline-treated control cultures, Sars-CoV-2 replicated efficiently, resulting in a rapid increase in viral titer.

In contrast, daily treatment with AM-301, beginning right before inoculation, showed effective protection against viral infection. 48 hours post-infection, average virus titers were 90.0% lower than those observed in controls (p<0.05). 72 hours and 96 hours post-infection, average virus titers were 99.2 and 99.4% lower, respectively (p<0.001). Even when unbound virus was not removed daily through apical washing, allowing the virus to accumulate in the culture for 4 days, the reduction in viral titer was 92.4% compared to saline-treated controls (p<0.001).