Scottish COVID-19 vaccine shows ‘strong immune response’ in early UK trials

A new vaccine to protect against COVID-19, being produced in Scotland, has shown a “strong immune response” in early trials in the UK, the country’s health minister said.

UK Health Secretary Matt Hancock said that the promising Phase I and II results mean that the Valneva vaccine, being developed at Livingston in Scotland, can now move to Phase III clinical trials.

The vaccine was found to be safe and generally well-tolerated, with no safety concerns identified by an independent data safety monitoring board.

“The UK government has funded these clinical trials and it is fantastic to see Valneva’s vaccine produces a strong immune response,” said Hancock.

“This vaccine will be made onshore in Livingston in Scotland, giving another boost to British life science, and if approved will play an important role in protecting our communities. I look forward to seeing the results of the upcoming phase three trial,” he said.

The company said the results showed the vaccine was “highly immunogenic with more than 90 per cent of all study participants developing significant levels of antibodies” to the coronavirus spike protein. The vaccine, called VLA2001, also induced T-cell responses, which help the body fend off a virus and determine long-lasting immunity.

“These results are very promising and provide renewed hope that a vaccine using a whole inactivated virus might provide strong protection against variants,” said UK Vaccines Minister Nadhim Zahawi.

“If the results from the Phase III clinical trials are positive and the vaccine meets the robust standards of safety, quality and effectiveness of our medicines regulator, the MHRA, this will be another powerful weapon in our arsenal to beat this pandemic,” he said.

In the early studies, three dose levels of VLA2001 (low, medium, high), based on a schedule of two doses with vaccinations three weeks apart, were evaluated in 153 healthy adults aged 18 to 55 years. There were no statistically significant differences between dose groups and no differences between first and second vaccinations in terms of “reactogenicity”.

The majority of Adverse Events (AEs), or reactions, were mild or moderate and only two subjects reported severe solicited AEs (headache and fatigue).

“These are great results from Valneva, particularly around the antibody and cellular responses generated and low numbers of adverse events, as these indicate good levels of immune responses among the participants to date,” said Clive Dix, Chair of the Vaccines Taskforce in the UK.

“The findings of 100 per cent levels of immunogenicity against the viral spike protein in the high-dose group is also encouraging. Inactivated virus vaccines are proven technologies that are often able to induce wide-ranging immune responses, and these promising data indicate that VLA2001 may continue this trend,” he said.

Based on the data assessed, the company said it has decided to advance the high dose into the Phase 3 clinical trial. Other trials, including booster trials, involving antigen sparing doses will also be evaluated.

Thomas Lingelbach, Chief Executive Officer of Valneva, added, “We are extremely pleased with these results which take us a step closer to providing an inactivated vaccine to help the global fight against COVID-19. “The world needs multiple vaccines as well as booster options. Given the potential advantages often associated with inactivated whole virus vaccines, we believe that VLA2001 has an important role to play. This includes potential modifications to the vaccine to address variants, using our existing manufacturing process.”

VLA2001 claims to currently be the only whole virus, inactivated, adjuvanted vaccine candidate in clinical trials against COVID-19 in Europe. It is produced on Valneva’s established Vero-cell platform, leveraging the manufacturing technology for the company’s licensed Japanese encephalitis vaccine, IXIARO.

The new vaccine consists of inactivated whole virus particles of SARS-CoV-2, which causes COVID-19, with high S-protein density, in combination with two adjuvants, alum and CpG 1018.

France-headquartered Valneva describes itself as a specialty vaccine company focused on the development and commercialisation of prophylactic vaccines for infectious diseases with significant unmet medical need.