Dynavax Doses First Participants in Phase 1 Clinical Trial of COVID-19 Vaccine

Dynavax Technologies Corporation (Emeryville, CA, USA) has dosed the first participants in the Phase 1 clinical trial to evaluate Clover Biopharmaceutical’s (Chengdu, China) vaccine candidate to prevent COVID-19 that contains the company’s CpG 1018 adjuvant.

Under their collaboration, Clover is advancing its COVID-19 S-Trimer vaccine (SCB-2019), which is based on its proprietary Trimer-Tag vaccine technology platform, while Dynavax is providing the company’s proprietary toll-like receptor 9 (TLR9) agonist adjuvant, CpG 1018. 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.

The Phase 1 randomized, double blind, placebo controlled, first-in-human (FIH) study will assess safety, reactogenicity, and immunogenicity of SCB-2019 at multiple dose levels, administered as two intramuscular 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. The Phase 1 study will evaluate SCB-2019 alone, SCB-2019 in combination with Dynavax’s CpG 1018 adjuvant combined with alum, and SCB-2019 in combination with a different adjuvant. Based on preclinical results demonstrating the ability of CpG 1018-adjuvanted SCB-2019 to elicit neutralizing antibodies in multiple animal species, the collaboration has been expanded to include clinical supply of CpG 1018 to Clover. Preliminary safety and immunogenicity results of the study are expected in August 2020.

“We are proud to contribute CpG 1018 to this global effort to rapidly develop an adjuvanted vaccine to prevent COVID-19,” said Ryan Spencer, Chief Executive Officer of Dynavax. “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.”

Related Links:
Dynavax Technologies Corporation
Clover Biopharmaceutical