Dynavax and Clover Biopharmaceuticals Announce Research Collaboration to Evaluate Coronavirus (COVID-19) Vaccine Candidate with CpG 1018 Adjuvant

• Dynavax is providing CpG 1018, the adjuvant contained in U.S. FDA-approved HEPLISAV-B vaccine, to support the rapid development of Clover’s COVID-19 vaccine
• Clover advancing evaluation of its protein-based coronavirus vaccine candidate (COVID-19 S-Trimer)

EMERYVILLE, Calif. & CHENGDU, China–(BUSINESS WIRE)–Dynavax Technologies Corporation (Nasdaq: DVAX), a biopharmaceutical company focused on developing and commercializing novel vaccines, and Clover Biopharmaceuticals, a China-based global clinical-stage biotechnology company focused on developing novel and transformative biologic therapies, today announced that they have entered into a research collaboration to develop a vaccine candidate to prevent COVID-19. Clover is advancing evaluation of its protein-based coronavirus vaccine candidate (COVID-19 S-Trimer) in preclinical studies. Dynavax is providing technical expertise and the company’s proprietary toll-like receptor 9 (TLR9) agonist adjuvant, CpG 1018, to support this initiative.

In late-January 2020, upon knowing the genomic DNA sequence of the newly identified SARS-CoV-2 virus, which causes a disease named COVID-19, Clover scientists started designing the viral spike (S)-protein construct and completed its gene synthesis. Utilizing its patented Trimer-Tag^© technology, Clover has produced a COVID-19 S-Trimer subunit vaccine candidate that resembles the native trimeric viral spike 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 a new coronavirus vaccine.

“At Clover, we are eager to begin evaluating the combination of our S-Trimer vaccine candidate and Dynavax’s CpG 1018 adjuvant, as we believe adjuvants could play an important role in developing a successful and widely-available vaccine for this pandemic,” said Joshua Liang, Chief Strategy Officer at Clover and co-inventor of COVID-19 S-Trimer vaccine. “Leveraging our proprietary^© Trimer-Tag technology, S-Trimer is being rapidly developed to support global efforts in combating the current and any future coronavirus outbreaks.”

CpG 1018 is the adjuvant used in HEPLISAV-B® [Hepatitis B Vaccine (Recombinant), Adjuvanted], an adult hepatitis B vaccine approved by the U.S. Food and Drug Administration (FDA). Dynavax developed CpG 1018 to provide an increased vaccine immune response, which has been demonstrated in HEPLISAV-B. CpG 1018 provides a well‑developed technology and a significant safety database, potentially accelerating the development and large-scale manufacturing of a COVID-19 vaccine.

“Successfully responding to this public health emergency will require a collaborative approach, combining technologies and sharing data, to rapidly develop a vaccine to prevent COVID-19,” commented Ryan Spencer, Chief Executive Officer of Dynavax. “We are proud to contribute to this global effort with the goal of supporting rapid development and enabling large-scale manufacturing through the utilization of CpG 1018 which has already been successfully implemented in an approved, marketed vaccine in the U.S.”

About the Novel Coronavirus SARS-CoV-2 (and COVID-19 Disease)

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 caused serious human infections of respiratory system. The virus, which causes a disease named COVID-19, has never before been found in humans. Since this outbreak was first reported in late-2019, the virus has infected over 334,000 people and has caused over 14,600 reported deaths (as of 23 March 2020). It has been declared a pandemic by the World Health Organization (WHO). Currently there is no vaccine available for COVID-19.

About COVID-19 S-Trimer Vaccine

Utilizing Trimer-Tag^© technology, 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.

About Clover Biopharmaceuticals

China based 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. Having raised more than US$ 100 million in total capital since 2016, Clover is utilizing its proprietary Trimer-Tag^© technology platform to develop novel biologics targeting trimerization-dependent pathways. Additionally, Clover is leveraging its in-house cGMP biomanufacturing capabilities to develop select biosimilars. For more information, please visit our website: www.cloverbiopharma.com.

About Dynavax

Dynavax is a commercial stage biopharmaceutical company developing and commercializing novel vaccines. The Company launched its first commercial product, HEPLISAV-B® [Hepatitis B Vaccine (Recombinant), Adjuvanted], in February 2018, following U.S. FDA approval for prevention of infection caused by all known subtypes of hepatitis B virus in adults age 18 years and older. Dynavax is also advancing CpG 1018 as an advanced vaccine adjuvant through research collaborations and partnerships. For more information, visit www.dynavax.com.

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Contacts

Contact – Clover Biopharmaceuticals

Joshua Liang, +86 028-63925705

joshua.liang@cloverbiopharma.com

Contacts – Dynavax
Nicole Arndt, Senior Manager, Investor Relations

narndt@dynavax.com
510-665-7264

Derek Cole, President

Investor Relations Advisory Solutions

derek.cole@IRadvisory.com