Active agent in Australian-developed nasal spray >99.5% active against the Omicron SARS-CoV-2 variant

The antiviral agent in VIRALEZE™ antiviral nasal spray,SPL7013,achieved >99.5% reduction of virus infectivity (the maximal possible reduction) against the highly contagious Omicron variant of SARS-CoV-2

SPL7013 showed potent antiviral activity and was virucidal against the Omicron variant

SPL7013 outperformed other antiviral agents used in marketed nasal sprays,including iota-carrageenan and nitric oxide,in the studies conducted at The Scripps Research Institute

The potent activity of SPL7013 against the Omicron variant is consistent with previous data demonstrating virucidal activity against multiple variants of SARS-CoV-2,including Delta,Alpha,Beta,Gamma,and Kappa

SPL7013 has also previously demonstrated potent antiviral activity against respiratory viruses,including influenza,RSV,and viruses that cause the common cold

VIRALEZE™ is registered in more than 30 countries,including in Europe,and available online in these and certain other markets

MELBOURNE,Australia,March 1,2022 -- In a major development for its VIRALEZE™ antiviral nasal spray,Starpharma (ASX: SPL) today announced that its potent antiviral agent,achieved the maximum possible virucidal effect against the highly transmissible Omicron variant of SARS-CoV-2.

This new data is consistent with previously reported data conducted at The Scripps Research Institute in the United States,where SPL7013 has now been shown to be highly active against all nine SARS-CoV-2 variants tested – including more than 99.5% reduction of infectious virus in the Omicron variant.

Internationally recognised virologist,Professor Philippe Gallay,at The Scripps Research Institute,said SPL7013 performed even better in blocking the more infectious Omicron variant of SARS-CoV-2than early variants such as Delta.

"This effect appears to be due to the mechanism of action of SPL7013 that involves interaction with multiple regions of the virus spike protein," said Professor Gallay. "Mutations in the highly infectious virus variants appear to have introduced even more potential binding sites for SPL7013 to interact with.

"Omicron has over 30 mutations in the spike protein that have made it extremely highly transmissible in the community. To suppress this transmission,we need to have additional tools that can block SARS-CoV-2 infection of the nose,and SPL7013 could play an important role."

In the antiviral assays,SPL7013 was approximately 30 times more potent than iota-carrageenan against the Omicron variant,which is currently in multiple marketed nasal sprays,and 70 times more potent than heparin,which is currently being contemplated as a nasal spray.

Starpharma CEO Dr Jackie Fairley commented,"Starpharma is pleased to see that SPL7013 is virucidal and achieved more than 99.5% reduction of infectious virus in the Omicron variant."

"SPL7013 has now demonstrated impressive performance against all five 'Variants of Concern' tested,and now also Omicron. The high level of activity against Omicron is entirely consistent with previous data for SPL7013,which has shown antiviral and virucidal activity in multiple viruses. This new data further illustrates SPL7013's breadth of activity and the potential real-world benefits of VIRALEZE™."

The data on the effect of SPL7013 against other SARS-CoV-2 variants was recently presented at the major international scientific meeting,Conference on Retroviruses and Opportunistic Infections (CROI) 2022 by Professor Gallay.[1]

VIRALEZE™ is registered in more than 30 countries,India,Vietnam,Saudi Arabia and New Zealand,and the nasal spray is also available in these regions and others online through viraleze.co.

In Vietnam,VIRALEZE™ is available through a number of major pharmacy chains that collectively have more than 1,300 stores.

[1]Gallay P,Luscombe C,Stauffer W,et al. Effect of astodrimer sodium against SARS-CoV-2 variants (α,β,γ,δ,κ) in vitro. [CROI Abstract 478]. Abstracts From CROI 2022 Conference on Retroviruses and Opportunistic Infections. CROI 2022 Abstract eBook. 2022;478.