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Clover’s Vaccine Candidate Reduced Household Transmission of SARS-CoV-2 in Study Published in Clinical Infectious Diseases

-- The study, a collaboration between Clover and the International Vaccine Institute, showed that a household contact was 84% less likely to get a SARS-CoV-2 infection when the infected household member had received SCB-2019 (CpG 1018/Alum) compared to placebo --

-- Results indicate that vaccination with SCB-2019 can potentially help control the spread of SARS-CoV-2 within communities through the reduction of transmission to household contacts and through previously demonstrated efficacy against SARS-CoV-2 --

-- SCB-2019 is among the first COVID-19 vaccines to demonstrate ability to significantly reduce SARS-CoV-2 transmission prospectively in a clinical study to date --

SHANGHAI, China and SEOUL, Republic of Korea, Nov. 30, 2022 (GLOBE NEWSWIRE) -- Clover Biopharmaceuticals, Ltd. (Clover; HKEX: 02197), a global clinical-stage biotechnology company developing novel vaccines and biologic therapeutics, and the International Vaccine Institute, an international nonprofit organization devoted to providing vaccines critical to global public health and based in Seoul, Korea, today announced that Clinical Infectious Diseases has published additional data from SPECTRA, a global Phase 2/3 clinical trial, that showed vaccination with SCB-2019 (CpG 1018/Alum) reduced the risk of transmitting SARS-CoV-2 infection to household members, compared to placebo participants.

“These results are important for public health officials striving to control future outbreaks and indicate that vaccination with SCB-2019 considerably reduces the risk of SARS-CoV-2 spreading within communities,” said Dr. Nicholas Jackson, President of Global Research and Development of Clover. “The new data on community-level impact further strengthens our confidence in SCB-2019 as a premier vaccine that can potentially play an important role in large-scale vaccination campaigns in China and globally.”

The study demonstrated that a household contact was 84% less likely to get a SARS-CoV-2 infection when the infected household member had received SCB-2019, compared to households where the infected household member was not vaccinated. Among the 134 household contacts of infected household members who had received SCB-2019, there was one case of COVID-19; among the 250 household contacts of infected household members who were not vaccinated, there were 12 cases.

“As the world grapples with new outbreaks and variants, IVI is proud to advance our scientific understanding of the benefits of COVID-19 vaccination beyond personal protection,” said Jerome Kim, MD, Director General of the International Vaccine Institute. “The clear takeaway from this study with Clover’s SCB-2019 is that vaccines with demonstrated safety and efficacy can reduce the risk of household transmission and should continue to play a central role in the ongoing global response strategy to COVID-19.”

There were no cases of symptomatic SARS-CoV-2 infection among household contacts who were partially or fully vaccinated and where the infected household member was vaccinated with SCB-2019. This indicates that SCB-2019 vaccination reduced household transmission and that vaccinated household contacts also likely benefited from the protection provided by their own vaccination.

This exploratory, prospective study was part of the SPECTRA Phase 2/3 trial and compared reductions in SARS-CoV-2 inflections in households and household contacts of SCB-2019 vaccine recipients with infections in households and household contacts of placebo recipients. The study was performed at eight Phase 2/3 SPECTRA sites in the Philippines. A total of 154 participants who received placebo or SCB-2019 and who subsequently experienced SARS-CoV-2 infection were enrolled in this study as were 388 of their household contacts. The study team was blinded to the assignment of SPECTRA participants to vaccine or placebo groups. Enrolled households and household contacts were monitored for three weeks to detect new COVID-19 infections. Symptomatic cases for participants and household contacts were confirmed with reverse transcriptase polymerase chain reaction (rRT-PCR) test, while asymptomatic cases were determined using anti-N antibody rapid antibody test kits.

Clover is working towards completing regulatory submissions to the China National Medical Products Administration, the European Medicines Agency, and the World Health Organization for SCB-2019 by the end of 2022, while concurrently preparing for its commercialization in China and globally upon receiving regulatory approvals.

About SCB-2019 (CpG 1018/Alum) 
Clover developed the SCB-2019 antigen, a stabilized trimeric form of the S-protein based on the original strain of the SARS-CoV-2 virus, and combined it with Dynavax’s (Nasdaq: DVAX) CpG 1018 advanced adjuvant and aluminum hydroxide (alum). Phase 2/3 data from 30,000+ participants across five countries showed that SCB-2019 (CpG 1018/Alum) achieved 100% efficacy against severe COVID-19 and hospitalization caused by all strains of SARS-CoV-2 circulating during the trial, and a potentially best-in-field safety profile. Clover is developing SCB-2019 (CpG 1018/Alum) as a universal booster candidate for potential use regardless of previous vaccination technology or infection history. To date, these trials have shown that SCB-2019 (CpG 1018/Alum) elicited a robust neutralization of variants including Omicron. Clover is pursuing regulatory approval of SCB-2019 (CpG 1018/Alum) with the China National Medical Products Administration, the European Medicines Agency, and the World Health Organization.

SPECTRA (Study Evaluating Protective-Efficacy and Safety of Clover’s Trimeric Recombinant Protein-based and Adjuvanted COVID-19 Vaccine) is a 1:1 randomized, placebo-controlled, double-blinded study to evaluate the efficacy, safety and immunogenicity of SCB-2019 (CpG 1018/Alum) compared to placebo in over 30,000 participants 18 years of age and older in five countries. Participants received SCB-2019 (CpG 1018/Alum) administered in a two-dose regimen, 21 days apart, or placebo.

About Clover Biopharmaceuticals
Clover Biopharmaceuticals is a global clinical-stage biotechnology company committed to developing novel vaccines and biologic therapeutics. The Trimer-Tag™ technology platform is a product development platform for the creation of novel vaccines and biologic therapies. Clover leveraged the Trimer-Tag™ technology platform to become a COVID-19 vaccine developer and created SCB-2019 (CpG 1018/Alum) to address the COVID-19 pandemic caused by SARS-CoV-2.

For more information, please visit Clover's website: and follow the company on LinkedIn and Twitter.

About the International Vaccine Institute (IVI)
The International Vaccine Institute (IVI) is a non-profit international organization established in 1997 at the initiative of the United Nations Development Programme with a mission to discover, develop, and deliver safe, effective, and affordable vaccines for global health.

IVI’s current portfolio includes vaccines at all stages of pre-clinical and clinical development for infectious diseases that disproportionately affect low- and middle-income countries, such as cholera, typhoid, chikungunya, shigella, salmonella, schistosomiasis, hepatitis E, HPV, COVID-19, and more. IVI developed the world’s first low-cost oral cholera vaccine, pre-qualified by the World Health Organization (WHO), and developed a new-generation typhoid conjugate vaccine that is currently under assessment for WHO PQ.

IVI is headquartered in Seoul, Republic of Korea with a Europe Regional Office in Sweden and Collaborating Centers in Ghana, Ethiopia, and Madagascar. 39 countries and the WHO are members of IVI, and the governments of the Republic of Korea, Sweden, India, and Finland provide state funding. For more information, please visit

Clover Forward-looking Statements
This press release contains certain forward-looking statements and information relating to us and our subsidiaries that are based on the beliefs of our management as well as assumptions made by and information currently available to our management. When used, the words "aim," "anticipate," "believe," "could," "estimate," "expect," "going forward," "intend," "may," "might," "ought to," "plan," "potential," "predict," "project," "seek," "should," "will," "would" and the negative of these words and other similar expressions, as they relate to us or our management, are intended to identify forward-looking statements.

Forward-looking statements are based on our current expectations and assumptions regarding our business, the economy and other future conditions. We give no assurance that these expectations and assumptions will prove to have been correct. Because forward-looking statements relate to the future, they are participant to inherent uncertainties, risks and changes in circumstances that are difficult to predict. Our results may differ materially from those contemplated by the forward-looking statements. They are neither statements of historical fact nor guarantees or assurances of future performance. We caution you therefore against placing undue reliance on any of these forward-looking statements. Any forward-looking statement made by us in this document speaks only as of the date on which it is made. Factors or events that could cause our actual results to differ may emerge from time to time, and it is not possible for us to predict all of them. Participant to the requirements of applicable laws, rules and regulations, we undertake no obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise. All forward-looking statements contained in this document are qualified by reference to this cautionary statement.

Clover Biopharmaceuticals:
Albert Liao
Executive Director, Corporate Communications

Elaine Qiu
Director, Investor Relations

International Vaccine Institute:
Aerie Em
Global Communications & Media Specialist
+82 2 881 1386 |  

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