Jefferies lab develops promising new ‘Gemini’ platform for vaccine and therapeutic delivery

By Emily Cook

Researchers from the lab of Dr. Wilf Jefferies, a professor in the Department of Microbiology and Immunology, Michael Smith Laboratories, Department of Medical Genetics, Centre for Blood Research, Djavad Mowafaghian Centre for Brain Health, and Department of Urologic Sciences at UBC have developed a new, versatile platform for delivering therapeutics and vaccines to patients that could reduce costs and improve access in the future.

Published in Nature Communications, the ‘Gemini’ platform has been a long-running project for the lab, developed as a departure from existing vaccine delivery systems and overcoming some of the challenges that exist with those methods.

“While there had been discussions about taking this new approach for a long time, we really got started on this project at the very beginning of the COVID-19 pandemic,” shares Kyung Bok Choi, head Research Technician in the Jefferies lab and a co-author of the study. “We saw the importance of testing this platform for emergency deployment against SARS-CoV-2 and other emerging infectious diseases.”

Gemini is a novel self-amplifying nucleic acid platform. Used as a vaccine, it delivers genetic instructions that prompt a patient’s own cells to make a protein from a chosen pathogen, such as a virus. The immune system learns to recognise that protein and mounts a protective response against the pathogen it came from, so the body is primed to fend off the real infection should it appear later.

The defining feature of Gemini is its flexibility. The same construct can be supplied as either RNA or DNA, and both forms are self-amplifying, so a small dose produces sustained, long-term expression of the protein rather than the brief burst that ordinary mRNA provides.

The second innovation is its packaging. Gemini can be used with or without a lipid nanoparticle carrier, removing manufacturing complexities and associated costs of production. Additionally, Gemini is far more stable and doesn’t need to be stored at minus 80 ºC, keeping it free of the deep freeze ‘cold chain’. This could help with providing vaccines to more rural and remote areas that don’t have the necessary equipment to keep vaccines cold.

“Vaccines developed with the Gemini platform can be stored at room temperature, and can survive multiple freeze-thaw cycles and be freeze-dried to a powder and reconstituted if necessary, which is especially helpful in transport and distribution,” explains Dr. Cheryl Pfeifer, a Research Associate in the Jefferies lab and study co-author. “With Gemini, there is much less worry about storage and vector stability than with other mRNA vaccines.”

Beyond SARS CoV-2 vaccines, the team is also developing the Gemini platform to deliver therapeutic proteins and antibodies, broadening its potential applications across medicine. This includes work to develop an anti-malarial therapeutic antibody for use in regions where malaria is endemic.

The results so far come from cell cultures and small and large animal studies, and several stages of testing remain before the platform is fully optimized and its applications confirmed in humans. Even so, they mark encouraging steps toward this goal.

“Several years of experiments and research projects, run by many different contributors, went into the development of this platform. One of the real advantages is speed, and the fact that this is genuinely a new kind of platform. Starting from an acute need, such as an emerging pandemic, we can go from designing a vaccine to creating a candidate vaccine in just a few weeks, with implementation soon after,” shares Dr. Suresh Kari, Jefferies lab Research Associate and another co-author on the study. “It’s a really exciting time for the lab, and we’re pleased to share these findings and to see where our next steps lead.”

We look forward to seeing this work progress, and the impact it could have through reduced costs and improved access.

The study’s authors disclosed that they hold financial interests in, and affiliations with, the UBC start-up company Eyam Health Inc., which helped fund this work.

This story was originally published by the Michael Smith Laboratories.