Coronavirus Vaccine Candidate Nears Pre-Clinical Tests

A China-based biotechnology company announced that it has entered into a research collaboration with GSK for its protein-based coronavirus vaccine candidate (COVID-19 S-Trimer). 

Announced in a press release published on February 24, 2020, GSK said it will provide Clover Biopharmaceuticals with its pandemic adjuvant system for further evaluation of S-Trimer in non-human clinical studies.

A highly purified form of the S-Trimer vaccine candidate is expected to be available for performing pre-clinical studies in about 2 months.

S-Trimer is a trimeric SARS-CoV-2 spike (S)-protein subunit vaccine candidate. 

Similar to other enveloped RNA viruses such as HIV, RSV, and Influenza, SARS-CoV-2 is also an RNA virus that has a trimeric spike (S) protein on its viral envelope. 

The trimeric S protein of SARS-CoV-2 is responsible for binding to host cell surface receptor ACE2 and subsequent viral entry, making it the primary target antigen for vaccine development. 

S-Trimer resembles the native trimeric viral spike protein and is produced via a rapid mammalian cell-culture based expression system.

Having one of the largest in-house, commercial-scale cGMP biomanufacturing capabilities in China, Clover could potentially rapidly scale-up and produce large quantities of this SARS-CoV-2 coronavirus vaccine candidate.

“Utilizing our proprietary Timer-Tag© technology has been shown to be recognized by antibodies produced by multiple previously-infected coronavirus patients, S-Trimer is being rapidly developed to support global efforts in combating this current and any future coronavirus outbreaks,” said Joshua Liang, Chief Strategy Officer and Board Director at Clover.

Trimer-Tag is an innovative drug development platform that allows the production of novel, covalently-trimerized fusion proteins. 

Major disease targets are trimerization-dependent such as the tumor necrosis factor superfamily (involved in extrinsic apoptosis, immune co-stimulation, and inflammation) as well as enveloped RNA virus antigens responsible for entry into host cells. 

Clover’s Trimer-Tag technology to create trimerized fusion proteins that are able to effectively target these previously undruggable pathways.

SARS-CoV-2 is a new coronavirus identified in late 2019 and belongs to a family of enveloped RNA viruses that include MERS and SARS, both of which cause serious human infections of the respiratory system.  

The SARS-CoV-2 coronavirus causes a disease recently named COVID-19, which has never before been found in humans.

As of February 24, 2020, China has reported the most COVID-19 cases and 2,596 related fatalities.

Furthermore, the US Food and Drug Administration has not approved any preventive or therapeutic vaccine for use against the SARS, MERS or the SARS-CoV-2 coronavirus.

Thomas Breuer, Chief Medical Officer of GSK Vaccines, said in the press statement, “The use of an adjuvant is of particular importance in a pandemic situation since it may reduce the amount of vaccine protein required per dose, allowing more vaccine doses to be produced and therefore contributing to protecting more people.”

GSK is a science-led global healthcare company with a special purpose: to help people do more, feel better, live longer. GSK is the leading manufacturer of vaccines globally. 

Clover Biopharmaceuticals is a global, clinical-stage, research-based biotechnology company focused on discovering, developing and commercializing transformative biologic therapies, with a focus on oncology and autoimmune diseases, as well as viral vaccines. 

Coronavirus vaccine development news can be found at Precision Vaccinations.