Published: 13-06-2023 11:38 | Updated: 13-06-2023 12:16

KI-developed COVID vaccine able to recognise mutated virus now being tested on humans

Person with gloves holds vaccine syringe.
Photo: Getty Images

A new DNA-based COVID-19 vaccine is now being tested for the first time on healthy volunteers at Karolinska University Hospital. The vaccine has been developed at Karolinska Institutet and target multiple parts of the virus, making it less vulnerable to mutated strains and potentially effective against new variants.

Matti Sällberg
Matti Sällberg. Photo: Erik Flyg

"This vaccine makes the immune system's reaction more similar to what it looks like in the event of a real infection compared to today's vaccines,” says Matti Sällberg, professor of biomedical analysis at the Department of Laboratory Medicine, Karolinska Institutet, in a press release from Karolinska University Hospital. “We hope that it will produce a broader immune response, which can be helpful for people who have difficulty forming antibodies because they are under dialysis or on immunosuppressants.”

Current COVID-19 vaccines target the virus’s so-called spike proteins, which the virus uses to hook onto cells to start an infection. It is therefore effective to develop vaccines against them, but also problematic since the spike easily mutates, which risks making the vaccine less potent.

“The new vaccine is based on parts of spike proteins from three different corona strains, but also targets two other parts of the virus that are more genetically stable,” says Professor Sällberg. “This makes it effective against Omicron and perhaps also future variants of the virus.”

While DNA vaccines have only recently begun to be used clinically, scientists have been researching them for over 20 years. The DNA vaccine now being tested at Karolinska University Hospital is an innovation by Professor Sällberg’s group at Karolinska Institutet supported by the EU and developed under the OPENCORONA project. Professor Sällberg is founder and co-owner of SVF Vaccines AB, which has patented the vaccine. 

Protection against new variants 

The clinical phase 1 study includes 16 healthy volunteers aged between 18 and 65, who are being monitored at the Phase 1 unit of the Center for Clinical Cancer Studies in Huddinge in collaboration with the Medical Unit for Infectious Diseases at Karolinska University Hospital. All participants received their third dose of the mRNA vaccine at least six months ago. Their health status and immunological response to the vaccine are being monitored for three months, including with a weekly COVID test.

Soo Aleman in front of the hospital entrance in Huddinge.
Soo Aleman. Photo: Erik Flyg

“It is important that we test this type of new vaccine that can provide a broader immune response and potentially offer better protection against new variants of COVID-19,” says Soo Aleman, adjunct professor and senior consultant at the Medical Unit for Infectious Diseases at Karolinska University Hospital. 

Administered with an electrical pulse

The fact that the vaccine is based on DNA has its advantages and disadvantages. Unlike mRNA, DNA does not require strict storage at -40 degrees Celsius. However, after the DNA vaccine is injected, an electric pulse, known as electroporation, needs to be delivered to the patient immediately to enable the DNA to enter the cell nuclei.

“A special instrument has been developed under the OPENCORONA project by our partner, IGEA, for use during DNA injection,” explains Professor Sällberg. “It’s called an EPSgun and delivers a small electric pulse. The arm may twitch slightly, but the feeling subsides quickly. The patients’ experience of the injection is recorded as an important part of the research.”

This project has received funding from the European Union´s Horizon 2020 research and innovation program under the grant agreement No 101003666.