Revelar Biotherapeutics and Twist Bioscience Announce RBT-0813 Neutralizes SARS-CoV-2 Omicron (B.1.1.529/BA.1) and Delta (B.1.617.2) Variants

Jan. 5, 2022 13:00 UTC

-- Results independently confirmed through live virus plaque-reduction assay --

-- Results published on BioRxiv and submitted to the FDA as part of pre-IND data package --


BETHESDA, Md. & SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)-- Revelar Biotherapeutics, Inc. and Twist Bioscience Corporation (Nasdaq: TWST) today announced that RBT-0813 binds to and neutralizes the Omicron and Delta variants of SARS-CoV-2 in live virus studies. RBT-0813 is an innovative bispecific antibody discovered by Twist Biopharma and licensed to Revelar Biotherapeutics that targets epitopes on the SARS-CoV-2 spike protein. Revelar continues to advance preclinical development of RBT-0813 to submit an Investigational New Drug application (IND) in the first half of 2022 to begin human clinical trials shortly thereafter.

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This new in vitro binding and neutralization data has been published on BioRxiv with a peer-reviewed publication of the data planned for early 2022. Binding and kinetic data were generated through Surface Plasmon Resonance (SPR) and independently confirmed by flow cytometry. The live virus plaque-reduction data were generated independently at the Yale School of Medicine in the laboratory of Dr. Akiko Iwasaki using live SARS-CoV-2 virus from ancestral, as well as the Omicron (B.1.1.529/BA.1) and Delta (B.1.617.2) variants of concern (VOC) isolated from patient nasopharyngeal specimens.

“We conducted studies demonstrating that RBT-0813 neutralized the Omicron and Delta variants at the concentrations tested,” commented Akiko Iwasaki, Ph.D., Waldemar Von Zedtwitz Professor of Immunobiology and Molecular, Cellular and Developmental Biology at Yale University and Investigator, Howard Hughes Medical Institute.

“With this data, we have now confirmed that RBT-0813 binds to and neutralizes both the Delta and Omicron variants of concern in pre-clinical laboratory testing,” said Glenn Marina, CEO of Revelar Biotherapeutics. “We are working diligently to complete preclinical and CMC development to support an IND and the initiation of clinical studies in humans. In parallel, we are in discussions with the U.S. Food and Drug Administration and expect to submit our IND in 1H2022.”

Emily M. Leproust, Ph.D., Chief Executive Officer and Co-Founder of Twist said, “We are encouraged by these positive results, building on data from peer-reviewed publications in Science and a recent publication in mAbs, that demonstrated Twist Biopharma’s ability to discover the individual antibodies used to build the bispecific RBT-0813. These new results indicate that RBT-0813 could potentially offer treatment for patients infected with the most prevalent strains of COVID-19 and further demonstrates Twist Biopharma’s ability to leverage its unique discovery platform and antibody engineering capabilities to discover innovative therapeutics to address some of the most difficult to treat diseases.”

About RBT-0813

RBT-0813 is a VHH bispecific antibody that binds to the RBD (receptor binding domain) and appears to bind also outside of the RBM (receptor binding motif) of the SARS-CoV-2 spike protein, making it potentially less prone to escape mutations which are often concentrated in the RBM. Originally discovered by Twist Biopharma, a division of Twist Bioscience, the antibody was licensed to Revelar Biotherapeutics in November 2021. Revelar is completing preclinical and CMC development in support of submitting an IND in 1H2022 and initiating clinical studies shortly thereafter.

About Revelar Biotherapeutics, Inc.

Revelar Biotherapeutics is a biopharmaceutical company focused on developing and commercializing breakthrough therapeutic antibody products that address critical unmet patient needs for COVID-19 and other therapeutic areas. The management team of Revelar Biotherapeutics has deep expertise and an extensive track record of high-quality clinical development, regulatory affairs, CMC, business development and operations with leading global pharmaceutical companies. Spun out of Twist Bioscience in November 2021 with initial antibodies targeting the treatment of COVID-19, Revelar has the ability to leverage the antibody discovery and optimization platform of Twist Biopharma to license additional antibodies to five non-COVID targets. The Company’s therapeutic areas of interest include oncology and infectious diseases. Revelar seeks to combine its clinical development and commercialization capabilities with Twist’s unique and innovative technology platform and the brightest minds from industry and academia, to unlock new target classes and accelerate the discovery and delivery of transformative antibody therapeutics to meet patients’ unmet needs. To learn more about Revelar Biotherapeutics, visit

About Twist Bioscience Corporation

Twist Bioscience is a leading and rapidly growing synthetic biology and genomics company that has developed a disruptive DNA synthesis platform to industrialize the engineering of biology. The core of the platform is a proprietary technology that pioneers a new method of manufacturing synthetic DNA by “writing” DNA on a silicon chip. Twist is leveraging its unique technology to manufacture a broad range of synthetic DNA-based products, including synthetic genes, tools for next-generation sequencing (NGS) preparation, and antibody libraries for drug discovery and development. Twist is also pursuing longer-term opportunities in digital data storage in DNA and biologics drug discovery. Twist makes products for use across many industries including healthcare, industrial chemicals, agriculture and academic research.

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Legal Notice Regarding Forward-Looking Statements

This press release contains forward-looking statements. All statements other than statements of historical facts contained herein are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements involve known and unknown risks, uncertainties, and other important factors that may cause Twist Bioscience’s actual results, performance, or achievements to be materially different from any future results, performance, or achievements expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, the risks and uncertainties of the ability to attract new customers and retain and grow sales from existing customers; risks and uncertainties of rapidly changing technologies and extensive competition in synthetic biology could make the products Twist Bioscience is developing obsolete or non-competitive; the retention of employees of acquired companies and the ability of Twist Bioscience to successfully integrate acquired companies and to achieve expected benefits, risks of third party claims alleging infringement of patents and proprietary rights or seeking to invalidate Twist Bioscience’s patents or proprietary rights; and the risk that Twist Bioscience’s proprietary rights may be insufficient to protect its technologies. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to Twist Bioscience’s business in general, see Twist Bioscience’s risk factors set forth in Twist Bioscience’s Annual Report Form 10-K filed with the Securities and Exchange Commission on November 23, 2021, and subsequent filings with the SEC. Any forward-looking statements contained in this press release speak only as of the date hereof, and Twist Bioscience specifically disclaims any obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise.


Revelar Biotherapeutics
Laurence Smith
EVP, CFO & General Counsel

Twist Bioscience
Angela Bitting
SVP, Corporate Affairs


Source: Twist Bioscience Corporation

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