Clover begins trials of COVID-19 vaccine with Dynavax and GSK adjuvants

The Chinese company Clover Biopharmaceuticals revealed the start of a randomized, double-blind, human stage Phase I placebo-controlled clinical study to evaluate the safety, reactogenicity, and immunogenicity of its potential SARS-CoV-2 vaccine candidate SCB-2019. This announcement nominated Clover as the sixth Chinese biopharmaceutical company launching a potential COVID-19 vaccine clinical trial.

Clover’s S-Trimer vaccine in combination with Dynavax and GSK adjuvants

Clover is developing its COVID-19 S-Trimer vaccine (SCB-2019) established on Clover’s patented Trimer-Tag© vaccine development technology, in a previously announced collaboration with the novel vaccine focused biotechnology company Dynavax, which is offering patented toll-like receptor 9 (TLR9) adjuvant agonist CpG 1018. The S-Trimer vaccine is also developed with the help of GSK’s pandemic adjuvant system offering high neutralizing antibody levels elicited in multiple animal species. In February 2020 GSK announced its collaboration with Clover to develop a COVID-19 vaccine and has now also co-announced the human trials start of the S-Trimer vaccine (SCB-2019) in combination with GSKs pandemic adjuvant system.

The adjuvant use is expected to enhance the immune response of Clover’s SARS-CoV-2 vaccine candidate S-Trimer vaccine (SCB-2019). This could be of key importance in a pandemic as it can decrease the number of antigens required per dose, boosting the manufacturing capacity and eventually providing global access to the live-saving COVID 19 vaccine.

Thomas Breuer, Chief Medical Officer, GSK Vaccines, said:

“Our deliberate approach is to combine our proven pandemic adjuvant technology with protein-based COVID-19 vaccine candidates from several collaborators. We believe this holds the promise to produce vaccines at scale, potentially benefiting billions of people. We are encouraged by the pre-clinical data of this adjuvanted COVID-19 vaccine candidate from Clover and look forward to reviewing the data from this first trial. If this trial is successful, we hope to be in a position to move into more advanced trials later in the year.”

On the 19th of June, Dynavax announced that the first participants have already been dosed to evaluate Clover’s vaccine candidate to prevent COVID-19 that contains the Dunavax CpG 1018 adjuvant.

Ryan Spencer, Dynavax CEO commented:

“We are proud to contribute CpG 1018 to this global effort to rapidly develop an adjuvanted vaccine to prevent COVID-19. CpG 1018’s ability to enhance the immune response, as successfully demonstrated in HEPLISAV-B, is expected to reduce the dose of antigen needed, helping ensure broader availability to patients. Additionally, an adjuvanted vaccine may be especially important for older adults and people with chronic conditions who are traditionally less responsive to vaccination and have the greatest risk of severe disease and death from COVID-19.”

Clover expects to enrol 150 participants

The Phase 1 human stage clinical trial has been initiated at Linear Clinical Research in Perth, Australia and will enrol around 150 healthy adult and elderly participants.

The Phase 1 trial is a randomized, double-blind, placebo-controlled, first-in-human (FIH) study to assess safety, reactogenicity, and immunogenicity of SCB-2019 at multiple dose levels, delivered as 2 intramuscular (IM) injections in approximately 90 adult healthy subjects 18 to 54 years of age and approximately 60 elderly healthy subjects 55 to 75 years of age.

This vaccine programme is sponsored by the Coalition for Epidemic Preparedness Innovations (CEPI). Each SCB-2019 dose level will be evaluated with and without adjuvant. Preliminary safety and immunogenicity results are expected in August 2020.

About COVID-19 S-Trimer Vaccine

S-Trimer is the Trimeric SARS-CoV-2 spike (S)-protein subunit vaccine nominee that uses Trimer-Tag © technology. SARS-CoV-2 is an RNA virus that has a trimeric spike (S) protein in its viral membrane resembling other enveloped RNA viruses such as HIV, RSV and Influenza. Generally, the Trimeric S protein SARS-CoV-2 is binding to the host cell surface receptor ACE2 and eventually penetrates into the host, inducing various sometimes fatal levels of immune response.

The S-Trimer simulates the native trimeric viral spike (S) protein. It is generated by a rapid mammalian cell-culture expression mechanism and is expected to trigger controlled immune response antibody production aiming durable immunity against SARS-CoV-2.

About Clover Biopharmaceuticals

Headquartered in China Clover Biopharmaceuticals is a global, clinical-stage research-based biotech company dedicated to the discovery, development and commercialization of transformative biologic therapies in the fields of oncology, autoimmune diseases, and viral vaccines. Clover is utilising its patented technology platform Trimer-Tag© to build novel biologics pursuing trimerization-dependent pathways. In addition, Clover is using its in-house cGMP biomanufacturing capability to grow selected biosimilars.

For more details, please visit: www.cloverbiopharma.com