Phase 3 results of Valneva COVID-19 vaccine candidate show high antibody response, tolerability

Results arrived this week for a Phase 3 trial of Valneva SE’s COVID-19 vaccine candidate, VLA2001, and they revealed neutralizing antibody activity greater than 95 percent, along with broad T-cell responses and significant tolerability.

It was reported that the inactivated, adjuvanted vaccine provided neutralizing antibody titer levels higher than those of a similar vaccine produced by AstraZeneca, among a participant pool of 4,012 people in the UK.

“The low levels of reactogenicity and high functional antibody responses alongside broad T-cell responses seen with this adjuvanted inactivated whole virus vaccine are both impressive and extremely encouraging,” Adam Finn, professor of Pediatrics at the University of Bristol and the trial’s chief investigator, said. “This is a much more traditional approach to vaccine manufacture than the vaccines so far deployed in the UK, Europe, and North America, and these results suggest this vaccine candidate is on track to play an important role in overcoming the pandemic.”

All participants in the trial were at least 18 years old. Among them, VLA2001 proved more tolerable than the AstraZeneca offering, with participants 30 years and older reporting fewer adverse reactions up to seven days after vaccination. About 73 percent saw injection site reactions, and 70 percent saw systemic reactions, compared to 91 percent for both among AstraZeneca recipients. No serious adverse events were reported.

Further, T-cell responses included broad antigen-specific IFN-gamma producing T-cells reactive to S, N, and M protein. Emergence of COVID-19 cases was similar between treatment groups, with no severe cases reported for either vaccine, even from new COVID-19 strains.

“These results confirm the advantages often associated with inactivated whole virus vaccines,” Thomas Lingelbach, CEO of Valneva, said. “We are committed to bringing our differentiated vaccine candidate to licensure as quickly as possible and continue to believe that we will be able to make an important contribution to the global fight against the COVID-19 pandemic. We are keen to propose an alternative vaccine solution for people who have not yet been vaccinated.”

Valnea has already begun rolling submission for initial approval of its vaccine with the UK’s Medicines and Healthcare products Regulatory Agency and plans to commence the same with the European Medicines Agency. Another pair of trials, one focused on children between 5 and 12 years old and another focused on booster performance, are currently being prepared.