December 14, 2022

Dyadic’s DYAI-100 COVID-19 Vaccine Study Published in a Leading Peer-Reviewed Scientific Journal

“Thermophilic Filamentous Fungus C1-Cell-Cloned SARS-CoV-2-Spike-RBD-Subunit-Vaccine Adjuvanted with Aldydrogel®85 Protects K18-hACE2 Mice against Lethal Virus Challenge”

  • Study supports:
    • Dyadic’s anticipated First-In-Human clinical trial designed to demonstrate clinical safety and immune response in humans for its DYAI-100 COVID-19 recombinant protein RBD booster vaccine candidate.
    • The C1-cell produced RBD-C-tag antigen strongly binds ACE2 receptors in vitro. Adjuvanted RBD-C-tag-based vaccine candidate (DYAI-100) demonstrates strong immunogenicity, and antiviral efficacy, including in vivo protection against lethal intranasal SARS-CoV-2 virus challenge in human ACE2-transgenic mice. No loss of body weight or adverse events occurred.
    • Further data from the study supports that the C1-cell production platform enables a straightforward manufacturing process that is both inexpensive, scalable, and easily transferable for local production, offering strong competitive advantages.
  • Study Concluded: “The results of the studies presented demonstrate the feasibility and practicality of rapidly and economically developing a safe, effective, protective, and inexpensive recombinant protein vaccine candidate based on the SARS-CoV-2 receptor-binding domain (RBD) glycoprotein expressed and produced from the C1-cell protein production platform.
  • 4th peer-reviewed publication in 2022 relating to antigens produced from C1-cells showing safety and efficacy in animal models.

JUPITER, Fla., Dec. 14, 2022 — Dyadic International, Inc. (“Dyadic”, “we”, “us”, “our”, or the “Company”) (NASDAQ: DYAI), announced today that its study titled “Thermophilic Filamentous Fungus C1-Cell-Cloned SARS-CoV-2-Spike-RBD-Subunit-Vaccine Adjuvanted with Aldydrogel®85 Protects K18-hACE2 Mice against Lethal Virus Challenge” has been published in VACCINES, a leading peer-reviewed scientific journal as part of the Special Issue “Vaccine Candidate against SARS-CoV-2”.

Conducted together with leading scientists from several other organizations, including VTT Technical Research Centre of Finland, the Israel Institute for Biological Research (IIBR), and Envigo Clinical Research Israel, this study exemplifies Dyadic’s focus building innovative microbial platforms to address the growing demand for global protein production and unmet clinical needs for effective and affordable biopharmaceutical products for human and animal health.

“Many of the newly evolving pathogens are zoonotic viruses and they are contributing to a global threat. Safe and effective vaccines that can be developed rapidly and economically manufactured in global quantities following an outbreak are required to effectively combat these diseases. The efficacy, protection and safety data reported from this study further supports the expansive library of data – demonstrating a novel approach for the C1-cell protein production platform to be broadly applied for rapid development and manufacturing of vaccines and antibodies for both human and animals,” said Dr. Ronen Tchelet, Dyadic’s Chief Scientific Officer.

Dr. Abraham Nyska, Fellow IATP Expert in Toxicological Pathology and co-author of the DYAI-100 toxicology data (Toxicologic Pathology 2022) stated, “this study demonstrates the excellent safety profile and lasting immunogenic response from Dyadic’s DYAI-100, recombinant protein receptor binding domain (RBD) COVID-19 vaccine candidate.”

A link to the scientific publication as published in the peer reviewed journal “VACCINES” can be found below:

“Thermophilic Filamentous Fungus C1-Cell-Cloned SARS-CoV-2-Spike-RBD-Subunit-Vaccine Adjuvanted with Aldydrogel®85 Protects K18-hACE2 Mice against Lethal Virus Challenge”

About DYAI-100

DYAI-100, also known as C1-SARS-CoV-2 RBD vaccine, is a novel receptor-binding domain (RBD) recombinant booster vaccine candidate, highly expressed in Dyadic’s proprietary C1-cell protein production platform for the prevention of COVID-19. The C1-SARS-CoV-2 RBD vaccine drug product consists of the SARS-CoV-2 RBD-C-tag adjuvanted with alum Alhydrogel 85® 2%. DYAI-100 is expected to start a Phase 1 clinical trial in South Africa in Q1 2023 to assess the safety, reactogenicity, and immunogenicity of the C1-SARS-CoV-2 RBD vaccine, administered as a booster, in healthy volunteers.

About Dyadic International, Inc.

Dyadic International, Inc. is a global biotechnology company committed to building disruptive microbial platforms to address the growing demand for global protein bioproduction and unmet clinical needs for effective, affordable, and accessible biopharmaceutical products for human and animal health.

Dyadic’s lead technology, its C1-cell gene expression and protein production platform, is based on the highly productive and scalable industrially proven fungus Thermothelomyces heterothallica (formerly Myceliophthora thermophila). C1-cell gene expression and protein production platform is currently used to speed development, lower production costs, and improve performance of biologic vaccines and drugs at flexible commercial scales for the human and animal health markets.

Dyadic is also developing the Dapibus™ filamentous fungal based microbial protein production platform to enable the rapid development and large-scale manufacture of low-cost proteins, metabolites, and other biologic products for use in non-pharmaceutical applications, such as food, nutrition, and wellness.

With a passion to enable our partners and collaborators to develop effective preventative and therapeutic treatments in both developed and emerging countries, Dyadic is building an active pipeline by advancing its proprietary microbial platform technologies, including our lead product DYAI-100 COVID-19 vaccine candidate, as well as other biologic vaccines, antibodies, and other biological products.

To learn more about Dyadic and our commitment to helping bring vaccines and other biologic products to market faster, in greater volumes and at lower cost, please visit

Safe Harbor Regarding Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, including those regarding Dyadic International’s expectations, intentions, strategies, and beliefs pertaining to future events or future financial performance, such as the success of our clinical trial our research projects and third-party collaborations, as well as the availability of necessary funding. Actual events or results may differ materially from those in the forward-looking statements because of various important factors, including those described in the Company’s most recent filings with the SEC. Dyadic assumes no obligation to update publicly any such forward-looking statements, whether because of new information, future events or otherwise. For a more complete description of the risks that could cause our actual results to differ from our current expectations, please see the section entitled “Risk Factors” in Dyadic’s annual reports on Form 10-K and quarterly reports on Form 10-Q filed with the SEC, as such factors may be updated from time to time in Dyadic’s periodic filings with the SEC, which are accessible on the SEC’s website and at


Dyadic International, Inc.
Ping W. Rawson
Chief Financial Officer

Primary Logo