5 June 2023

New vaccine concept against SARS-CoV-2 successfully tested

Researchers at the University of Basel, in collaboration with Rocketvax AG, a subsidiary of Swiss Rockets AG, have developed a new approach for a vaccine against COVID-19. This vaccine is based on a modified coronavirus that can enter body cells and trigger an effective immune response but cannot multiply in the body. In animal studies, the vaccine effectively protected against the disease and prevented virus transmission. The mechanism of action for the single-cycle virus approach has been successfully confirmed, and further preclinical studies will select the clinical candidate.

Although safe and effective COVID-19 vaccines have been available since early 2021, SARS-CoV-2 continues to spread, with new variants continuously emerging. New vaccines that are easy to store and administer and that build up effective immune protection are an essential step toward keeping the SARS-CoV-2 coronavirus at bay in the long term.

Researchers led by Prof. Thomas Klimkait at the University of Basel and in collaboration with Rocketvax AG, are now presenting a vaccine concept that could lead to a new generation of vaccines against SARS-CoV-2. This concept can also be potentially adapted to new variants and other viruses. The promising results are now being submitted to a peer-reviewed journal for publication.

“Single-cycle virus” is how the researchers describe the principle of their novel vaccine. The new vaccine is based on a specially adapted version of the virus that can be produced in the laboratory. In cells of the vaccinated person, however, the single-cycle virus cannot replicate further after the initial entry. For their vaccine, the researchers modify the genome of the virus and make the virus replication incompetent.

Prof. Thomas Klimkait explains: “Among other things, we remove a specific gene from the blueprint for the viral envelope. No new virus particles can be formed if this envelope component is missing. Yet, the body cells still produce the remaining components of the virus and present them on their surface to the immune system, which recognizes the viral components and builds up effective and long-lasting immune protection.”

For humans, the plan is also to administer the vaccination by nose. In addition, as the single-cycle virus is highly stable, the vaccine can be stored in the refrigerator for long periods of time, says Klimkait. The research team is now planning to finalize the preclinical development with the potential to move with the vaccine production for a human clinical trial with a small cohort of subjects in Switzerland.

Dr. Vladimir Cmiljanovic, CEO of Rocketvax AG, says: "The positive test results are an important step in the development of a safe and easy-to-administer vaccine that can be quickly adapted to new virus variants."

The researchers have applied for a patent on the vaccination system. The new vaccine's research and development took place with Rocketvax AG and was financially supported by the InnoSuisse grant and the University Hospital of Basel. Proof-of-concept preclinical trials were conducted at the Friedrich-Loeffler-Institute in Germany. This collaboration is embedded in a research partnership with the University Hospital of Basel (UHBS) and the Swiss Tropical and Public Health Institute (Swiss TPH).

One can find more scientific information about the mechanism of action of the replication-incompetent SARS-CoV-2 virus in the University of Basel press release.


About Swiss Rockets AG

Founded in 2018, Swiss Rockets AG is implementing a paradigm shift in healthcare. Patients benefit from new therapies developed with innovative and pioneering methods. The Swiss Rockets AG team combines expertise and experience to create innovative medicines focused on cancer and viral diseases.

The founders of Swiss Rockets AG are Dr. Vladimir Cmiljanovic, Dr. Natasa Cmiljanovic, Manuel Ebner, Dr. Thomas Sander and Dr. Thomas Staehelin. Vladimir Cmiljanovic is the CEO, a medicinal chemist, and an entrepreneur with more than 15 years of experience in cancer drug development. He is the founder of the Swiss biotech companies PIQUR AG, TargImmune AG, Swiss Rockets AG, Rocketvax AG and Torqur AG. With his sister Dr. Natasa Cmiljanovic, the Chief Scientific Officer of Swiss Rockets AG, he has developed cancer drugs at the University of Basel. He has also founded and managed several biotech companies. Manuel Ebner is a Managing Director at Bank of America Merrill Lynch, Switzerland, and a strategic advisor to Swiss Rockets AG. Dr. Thomas Sander, one of the first employees of the biotech company Actelion, is a scientific advisor to Swiss Rockets AG. Dr. Thomas Staehelin, the co-founder of Swiss Rockets AG, is a member of the Executive Board and Chairman of several shareholder companies and foundations.

Members of the Board of Directors of Swiss Rockets AG are Dr. Vladimir Cmiljanovic (Chairman), Prof. Dr. Michael N. Hall, a renowned researcher and professor at the Center for Molecular Biosciences at the University of Basel, Dr. Natasa Cmiljanovic, a medicinal chemist and clinical scientist with experience in the development of cancer drugs, Dr. Thomas Ladner, a business lawyer, founder and co-founder of several successful start-ups and the World.Minds Foundation, André Debrunner, a financial expert and fund manager at Northern Trust Switzerland AG, and Christoph Brutschin, former Government Council of the Canton of Basel-Stadt and former Chair of the Canton’s Conference for economic affairs.


About Rocketvax AG

Rocketvax has its foundation in the ties between Swiss Rockets AG, a Swiss incubator and accelerator for startups with innovative therapies, and a team of expert scientists from the Universities of Basel and Zurich, the ETH Zurich, the University Hospital Basel, the Swiss Tropical and Public Health Institute in Basel, and Gigabases Switzerland AG, a spinoff of ETH Zurich.

RocketVax’s first group of vaccines addresses the SARS-CoV-2 virus and are currently undergoing preclinical testing while preparing for the production of the vaccines for human clinical trials. At Rocketvax, proprietary molecular biology technologies are used to develop novel vaccines for infectious diseases like COVID-19, cancer, and auto-immune disorders. Several vaccine candidates in the pipeline are being developed. They include the original live, single-cycle virus vaccine, live-attenuated vaccines against SARS-CoV-2, and a vaccine candidate against cancer.