CyanVac Announces Data from Preclinical Studies of Intranasal PIV5-based COVID-19 Vaccine Candidate CVXGA1

ATHENS, Ga. and LOS GATOS, Calif., June 9, 2022 /PRNewswire/ -- CyanVac LLC, a clinical-stage biopharmaceutical company developing intranasal vaccines using a proprietary transformational parainfluenza virus 5 (PIV5)-based vector, today announced preclinical data in a hamster model using CVXGA1, a COVID-19 vaccine candidate currently in Phase 1 clinical trials. The data show that CVXGA1, which expresses the Spike protein from the original strain (WA1) of SARS-CoV-2 (the virus that causes COVID-19 disease), provides broad protection against other SARS-CoV-2 strains including alpha, delta and omicron variants. In the hamster model, a single intranasal dose of CVXGA1 induced broad serum neutralizing antibodies against, and protected animals against disease challenge by, the WA1 and other strains. In addition, hamsters that received CVXGA1 as a single intranasal booster dose after two doses of an mRNA-based COVID-19 vaccine had higher levels of neutralizing antibodies against multiple SARS-CoV-2 strains than hamsters who were boosted with a third mRNA-based COVID-19 vaccine dose, and were also better protected against viral challenge.

The manuscript describing these data, entitled "Efficacy of Parainfluenza Virus 5 (PIV5)-vectored Intranasal COVID-19 Vaccine as a Single Dose Vaccine and as a Booster against SARS-CoV-2 Variants," is available on a preprint server at and has been submitted for potential publication in a peer-reviewed scientific journal.

"We are excited to see that our intranasal vaccine candidate, though based on the ancestral strain, can provide broad protection against different SARS-CoV-2 variants," said Dr. Biao He, founder and CEO of CyanVac. "What's more, it provides robust protection when used as a single dose booster for previously vaccinated hamsters. If similar effects are seen in humans, it could make our PIV5-based intranasal COVID-19 vaccine a compelling alternative to injectable vaccines."

"This work also highlights the 'plug and play' capabilities of our proprietary PIV5 platform," said Hong Jin, PhD, Chief Scientific Officer of CyanVac. "We have successfully generated and tested additional candidate vaccines encoding the Spike protein from variants like delta and omicron, and also a candidate vaccine that encodes both the COVID Spike and nucleocapsid proteins. This demonstrates that we can rapidly respond to emerging variants."

In the preclinical studies, hamsters were immunized with a single intranasal dose of CVXGA1, and levels of serum neutralizing antibodies against WA1, delta, and omicron were measured at 36 days and 108 days after immunization. Robust neutralizing antibody responses against all three strains were observed at both time points. Additional hamsters were immunized with CVXGA1 followed by challenge with the WA1, alpha, or delta strain. CVXGA1 protected against disease from all three strains, as assessed by change in body weight during the first 5 days after challenge, and by measurement of viral load in the lungs at day 5 by quantitative PCR and plaque assay for infectious virus. (Note that challenge infection using an omicron strain was not performed because omicron is less virulent than the other strains in hamsters.)

In addition, the ability of CVXGA1 to serve as a booster for mRNA-based COVID-19 vaccines was investigated. Hamsters were immunized with two doses of an mRNA-based COVID-19 vaccine 28 days apart. On day 91 after the initial immunization, the animals received a booster dose of either the same mRNA-based vaccine, a placebo, or an intranasal PIV5-based COVID-19 vaccine (CVXGA1 or other experimental vaccine). Serum neutralizing antibody responses against WA1, delta, and omicron (assessed at day 108) were more than seven-fold greater in the CVXGA1-boosted animals than in those that were boosted with the mRNA-based vaccine. When challenged with a SARS-CoV-2 delta variant on day 116, the CVXGA1-immunized animals were better protected against COVID-19 disease than animals that had been boosted with the mRNA-based vaccine, as assessed by change in body weight over 5 days post-challenge and viral load in lung homogenate by quantitative PCR.

CVXGA1 is currently in a Phase 1 clinical trial evaluating the safety and immunogenicity of a single intranasal dose. The trial is led by principal investigator Paul Spearman, MD, Albert B. Sabin Professor and Director of Infectious Diseases at Cincinnati Children's Hospital Medical Center.

About CVXGA1

CVXGA1 is a clinical-stage COVID-19 vaccine candidate based on CyanVac's proprietary parainfluenza virus 5 (PIV5) vector that encodes the spike (S) protein of SARS-CoV-2. The PIV5 vector itself is a respiratory virus that is not known to cause disease in humans, although it has been commonly administered to dogs as part of combination distemper / kennel cough vaccines for decades. CyanVac and its subsidiary, Blue Lake Biotechnology, Inc., are developing CVXGA1 as a single dose, intranasal vaccine to prevent SARS-CoV-2 infection and serious complications associated with COVID-19. Preclinical studies have demonstrated that CVXGA1 is immunogenic, protective, and prevents contact transmission of SARS-CoV-2.

Learn more about the ongoing Phase 1 clinical trial of CVXGA1 at

About CyanVac and Blue Lake Biotechnology

CyanVac LLC and its subsidiary, Blue Lake Biotechnology, Inc., are technology-driven companies developing lifesaving vaccines based on a proprietary PIV5 vaccine platform licensed from the University of Georgia. Our lead COVID-19 vaccine program is in Phase 1 clinical trials. Our second program targeting respiratory syncytial virus (RSV) will soon initiate a first-in-man Phase 1 study and has been granted Fast Track designation by FDA. In addition, the companies have early-stage proof of concept vaccine programs targeting norovirus and Lyme disease. CyanVac and Blue Lake Biotechnology are headquartered in Athens, Georgia, with a second site in Los Gatos, California.

Learn more at

Forward Looking Statements

This press release contains forward-looking statements, including with respect to the clinical development of CVXGA1 for COVID-19, a prophylactic vaccine to prevent COVID-19, which are subject to a number of risks, uncertainties and assumptions, including, but not limited to the timing and success of clinical trials and potential complications thereof; the ability to obtain and maintain regulatory approval; the labeling for any approved product; the scope, progress and expansion of developing and commercializing a product candidate; the size and growth of the market(s) and the rate and degree of market acceptance thereof vis-à-vis alternative therapies; the establishment and maintenance of any applicable collaborations; and the ability to achieve business development transactions on favorable terms to the Company, if at all. In light of these risks and uncertainties, the events and circumstances discussed in such forward-looking statements or which are other made by or on behalf of CyanVac and/or Blue Lake Biotechnology may not occur, and CyanVac's and/or Blue Lake Biotechnology's actual results could differ materially and adversely from those anticipated or implied thereby. Factors which may affect CyanVac's and/or Blue Lake Biotechnology's results include, but are not limited to, uncertainties and/or unexpected results related to research and development and clinical testing, the timing, costs and uncertainty of obtaining any required regulatory approvals, changes in the regulatory landscape, uncertainties related to obtaining additional capital as needed to meet CyanVac's and/or Blue Lake Biotechnology's needs on acceptable terms, or at all, the absence of any guarantee of product demand, market acceptance or competitive advantage for any of CyanVac's and/or Blue Lake Biotechnology's product candidates, if approved, and certain trade, legal, social and economic risks. Any forward-looking statements in this release speak only as of the date of this press release and are based on information available to CyanVac as of the date of this release, and neither CyanVac nor Blue Lake Biotechnology has any obligation to update or revise any such forward-looking statement.


CyanVac LLC and Blue Lake Biotechnology, Inc.
Gary Titus
Chief Financial Officer
(650) 862-9757

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